#1 - Comparison Phase - Documentation
by Michele Triplett, King County Sheriff's Office

Disclaimer:  The intent of this is to provide thought provoking discussion.  No claims of accuracy exist. 

Question – Comparison Phase - Documentation:

Did you document what your conclusion was based on (did you chart it, draw it, or include a written explanation)?

Possible Answers:

a)      No.

b)      Yes, our office does this for every individualization.

c)      No, I have never done this.

d)     No, it’s not in our operating policies to do it.

e)      No, we don’t have the manpower to do this.

f)       No, it wasn’t needed in this case.

g)      No, we don’t document what we see because we don’t want to influence others.

h)      Under ASCLD, the latent lift is considered sufficient documentation.

Discussion:

Answer a:  Previously, it was recommend to answer with a simple ‘yes’ or ‘no’ but that isn’t as acceptable as it once was.  If you just answer the above question with ‘No’ then it appears you did a less than acceptable job….that your work was lacking. 

Answer b:  Perhaps some people make a chart for every individualization.  This may look like a good practice but it’s not needed.  It may look like you’re being thorough when you’re really just wasting time by doing unnecessary steps. 

Answers c, d, and e:  These are excuses and it leaves people with the impression that you should have done some form of documentation.

Answer f:  I feel the best answer is f; documentation wasn’t done because it wasn’t needed.  We all have our own standards, agency standards, and industry standards but the most accepted standard is the scientific standard.  Science doesn’t require documentation for simple conclusions (stating that 8x8 is 64 is good enough; I don’t have to document each tick mark.  But if I’m ever asked to produce documentation, I should be able to).  It’s also important to note that science doesn’t require contemporaneous documentation on simple conclusions like this.  When conclusions are more complex, then documentation should go along with the conclusion so others know the conclusion had good justification behind it.

Answer g:  This may sound like a good answer but it’s really just an excuse for not understanding or following scientific protocols.  Science requires that conclusions be documentable in case anyone should ever ask for them.

Answer h:  The first thing to notice about this answer is that they use the term ASCLD instead of ASCLD/LAB.  It’s always more professional to use the correct name of an organization (preferably not the acronym).  This answer also seems to misunderstand the question.  Documentation of the physical evidence found is very different from documentation of the justification behind an analytical conclusion.  The latent print itself cannot be sufficient justification for a conclusion.

Answer f: This is the most comprehensive answer.

Answer i:  This is the standard of what is needed for an individualization but it doesn’t state how much is needed.

#8: Question – Prominent Cases:

Any questions about a prominent case (the Langill case, the Bryan Rose case, the Mayfield case, the Plaza decision, the Ricky Jackson case, etc).



Possible Answers:

a) The judge in the Rose case made a bad decision.

b) I wasn’t involved in the Mayfield case and I can’t speak about it without direct knowledge.

c) I’ve read the official court documents and I know that…….

d) That case happened years ago. At the time it occurred I read all the reports about it but I don’t recall the exact information right now.



Discussion:

Answer a: Don’t get caught repeating what you’ve heard. If you start to talk about a particular case then the attorney’s assume you can answer other questions, like why that was your answer. You don’t want it to end with you saying, “Well, that’s what I’ve heard”.

Answer b: While it’s not recommended for people to testify to rumors, it’s also not recommended to avoid speaking about these cases. Some cases are very prominent and a great deal of information has been published about these cases (information beyond speculation). If you can’t testify to the basic information on these cases then it could be interpreted that you’re not as knowledgeable as an expert should be.

Answers c or d: These answers are honest and professional. Examiners should try to remain as objective as possible when speaking of these cases.

#9: Question – On-Line Forums:

This could relate to any information on the internet or information in a newspaper article.

Possible Answers:

a)      An on-line chat board may not be a reliable source of information because answers aren’t always as accurate or as comprehensive as they should be.

b)      An on-line chat board may not be a reliable source of information because the answers may just be someone’s opinion and may not be tested or valid.

c)      I’d have to read the entire thread to understand the context of this conversation.

d)     I’m unfamiliar with forum and cannot comment on what was said.

e)      Yes, I did say that but I meant…..

f)       I can’t comment on this because I don’t know if they were referring to a specific incident, a specific case, or rules that only affect a specific jurisdiction. 

g)      I am aware that this was said but I don’t know what this person was basing this information on.

h)      I’ve seen this image on the internet but I can’t vouch for the authentication of the image. 

Discussion:

I’ve heard several people state that attorney’s are bringing up information from on-line forums during interviews or testimony.  Some people use this as a reason not to post on these forums and others use this as a way to slight those who do post.  On-line forums or blogs can be very informative and therefore I don’t believe people should discourage their use.  It’s more important that we understand the context of the information and not be afraid to answer to this if this comes up in court.

Answers a, b, c, d, f, g and h:  These are all appropriate answers.

Answer e:  I would discourage any discussion that sounds like the examiner is being defensive.  These on-line forums are a valuable source of information but need to be kept within the appropriate context.  Although they may be valuable at a specific time for a specific topic, the information from these conversations may not be as useful during a trial or to determine the expertise of a practitioner.

#10: Analysis phase of ACE-V
Question – Analysis Phase:

Can you explain the Analysis phase of ACE-V?

Possible Answers:

a)      I’m looking for sufficiency, to see if there’s enough for me to work with.

b)      I’m looking to see how much level 1 detail, level 2 detail, and level 3 detail exists and I determine if there’s enough for me to move on to the comparison phase.

c)      I’m collecting information which includes orientation, direction, ridge flow, pattern type, ridge color, clarity (contrast level, distortional aspects).

Discussion:

The analysis phase can be described in a variety of ways.  My initial thought is that it’s not really important how you describe it, but the truth is that if several people are testifying in the same case (which is happening more and more every day) and they describe anything differently then it appears as though there’s not a uniform method.  The difference in explaining something could also make it appear that one of the practitioners isn’t as knowledgeable as they should be.  To insure this isn’t the interpretation left in court we do need to have similar explanations.

Answer a:  This isn’t a bad answer but it really doesn’t describe the analysis stage.  I think it describes a pre-analysis stage or a quick assessment of what may be on a lift card.

Answer b:  This isn’t a bad answer either but it brings in a lot of terms that the court may not be familiar with.  Using an answer like this may result in you having to do a lot more explaining than is necessary.

Answer c:  This is a simple answer that can easily fit into most agencies use of the analysis phase.  It states ‘what’ you’re doing (collecting information) without stating ‘how’ it should be done.  This would fit agencies that print pictures of a latent print and mark the level 2 details and it would also fit agencies that just do a visual inspection.  This conclusion also conforms to the scientific method of hypothesis testing (where the first stage is to collect data).

Comparison phase - is ACE a linear or circular process?
by Michele Triplett, King County Sheriff's Office

Disclaimer:  The intent of this is to provide thought provoking discussion.  No claims of accuracy exist. 

#11: Question - Comparison Phase - Is ACE a linear or circular process?

When you did your comparison did you go back and forth between the latent and the known print?

Possible Answers:

a)      No, because that would create circular reasoning.

b)      No, because if you do this then you’re at risk for making the latent print fit the known print.

c)      Yes, I move back and forth between the latent and the known.

d)     Yes, I move back and forth between the latent and the known print, confirming the characteristics between the images are the same.

Discussion:

This question is implying that bias is created if you don’t do a full analysis of the latent print prior to moving to the comparison phase.  The key factors in arriving at a conclusion of individualization are consistency between the two prints and a sufficient amount of information to arrive at that conclusion.  ‘When’ someone noticed a characteristic was consistent isn’t a factor in establishing if that characteristic can or should be used.  The decision to use a characteristic should be based on the reproducibility of that feature and any visual distortional information that may go along with that characteristic.

Answer a:  Going back and forth is a circular process which is different than circular reasoning. 

Answer b:  Going back and forth may increase the tendency to make the latent fit the known print and as experts we need to understand this phenomenon and account for it.  Scientific methods allow us to use a circular process as long as we understand the shortcomings and protect against them when it’s needed (perhaps with blind verification or peer review).

Answer c:  Some books and articles promote using ACE as a linear process to prevent bias from being introduced into the comparison process.  This will diminish bias but too much valuable information can be lost by using ACE in a linear fashion.  Science promotes using a circular process by encouraging re-evaluating your own work as well as re-evaluation of the work of others.  Science also promotes going back to the beginning of any experiment and collecting more information to test your conclusion.  Science accounts for any bias that could be introduced by using other quality assurance measures.

Answer d:  This answer is the same as c with the additional ‘confirmation’ statement added.  This word should be avoided because scientific methods discourage confirmation and promote trying to falsify what we think is true.  Trying to falsify our beliefs will insure we aren’t drawn into biasing factors and insures we aren’t trying to make the images match.

#12: Question – Concerns over Blind Verification:

What would some concerns be when doing blind verification?

Possible Answers:

a)      Since the original evidence has the conclusions written on it, how do we recreate the evidence and not jeopardize the quality of the images.

b)      If we use reproduced images then it’s not a true representation of the original evidence.

c)      It’s time consuming and we don’t have the time to do this on every case.

d)     One concern is that people think blind verification is the best quality assurance measure but it doesn’t look at the reasons behind a conclusion, which is a scientific protocol.

e)      Blind verification has a place in looking at reliability but it shouldn’t be used as a replacement for peer review.

Discussion:

This is the perfect opportunity to say that blind verification isn’t the best quality assurance measure.  It looks for reliable conclusions but it doesn’t insure the principles and methods used were reliable enough to be used.

Answers a and b:  We may not be able to reproduce images that are exactly like the originals but it is possible to duplicate images so they’re an adequate representation of the of the originals.

Answer c:  This is a truthful statement but it disregards the fact that blind verification isn’t needed in every case.  Blind verification is a tool to protect against bias and bias is only a problem when alternative conclusions are plausible (in complex comparisons).

Answers d and e:  I think both of these answers educate the courts about blind verification.

#13: Question – Documentation - Levels of Details:

What levels of details did you use to make your identification?

Possible Answers:

a)      I used all the levels of details; I assess everything prior to arriving at a conclusion.

b)      I couldn’t say because we don’t document that information.

c)      Simple conclusions are arrived at by analyzing the quantity, the quality, the rarity, and the spatial placement of the level two details.  I may notice the level 1 and level 3 details but I don’t document it in my notes unless I specifically used it to make my individualization.  Since I didn’t note it, it wasn’t needed to make this individualization.

d)     I documented in my notes that the level 1 detail was consistent, the level 2 detail was consistent and sufficient to establish an individualization, and very clear level 3 detail (pores and ridges edges) was also visible but not needed to make the individualization.

e)      The definitions for the levels of details are slightly vague.  One person may label an short incipient ridge as level 3 detail because it may not always be visible and another person may label it as level 2 detail because it’s a ridge ending.  Regardless of what people call these characteristics, I noted that the ridge flow, the ridge events, and the ridge shapes were within the tolerance that we normally see.

Discussion:

One topic for discussion regarding this question is the use of the term ‘identification’ vs using the term ‘individualization’ (but that’s a topic for another discussion).

Answer a:  Although this may be true, it sounds suspicious when people testify to small details that happened 3 years ago without these details being documented.  Big details are usually memorable but remembering small details, like whether or not you used all the levels of details to make an individualization, is hard for most people to believe.

Answer b:  This may be a correct answer but it would sound better if the courts knew whether noting this information is needed or not.  Without stating that it isn’t needed, many people assume it wasn’t noted but it should have been.

Answers c, d, and e:  These are all good answers but I like c the best because d and e both may include excess documentation that isn’t needed (the necessity of such notes should be based on the complexity of the comparison).  Stating that documentation isn’t always needed could be important for different reasons; primarily so agencies that don’t have the time for excess documentation don’t feel pressured into adding a process that isn’t scientifically recommended, and when testifying in a trial with other experts we don’t want it to appear that there are different standards.

#14: Question – Verification – Explanation:

Why does the verifier know the results of the first examiner?

Possible Answers:

a)      It’s a time saving measure.

b)      You have to know the previous conclusion so you can try to prove that conclusion wrong.  Trying to prove something wrong helps diminish bias.

c)      Without knowing the results you can’t review if the information is correct.  This includes checking whether the conclusions being reported are accurate, whether proper procedures were followed, and if the conclusions were drawn from the data that was available. 

Discussion:

Answer a:  This is the most common answer and even though knowing someone else’s conclusion does save time, it’s not a concern of the verifier.  Confirming a previous conclusion is scientifically acceptable with simple conclusions but with complex situations then a conclusion needs more weight behind it than merely confirming the conclusion.  When complex situations arise, the conclusion is given more weight if the verifier corroborates the conclusion and insures that it was arrived at using appropriate principles.  The only way to scrutinize a conclusion in this way is by knowing the first examiners conclusion.

Answers b and c:  These answers are both good answers but answer c is a little more comprehensive.

#15: Question – Proficiency Testing:

What are proficiency tests testing for?

Possible Answers:

a)      Proficiency tests are a critical tool for evaluating a laboratory’s overall performance.

b)      Proficiency tests are testing to see if an examiner can arrive at accurate conclusions.

c)      Proficiency test are something that is done to help you comply with accreditation.

d)     Proficiency tests are testing to see if an examiner can make individualizations.

e)      Proficiency test can help get advanced warning of potential performance problems.

f)       Proficiency tests are testing to see if examiners can orient latent prints, locate a potential source of the latent print, and individualize the latent print.

g)      Proficiency tests are testing to see if a practitioners or laboratories can find answers that others would arrive at (consensus answers).

Discussion:

The CTS tests can be administered in several different ways.  Individual offices can require justification behind conclusions and agencies can require that examiners state the reason for a non-individualization.  A non-individualization could be due to an exclusion, due to an insufficient amount of information, or due to an inability to orient and locate the latent print.  The answers below are not considering how individual offices are using the CTS test but only looking at how CTS is using the test.

Answer a:   This is stated on the CTS website.  While it is a critical tool for evaluating the ability to make individualizations, it doesn’t test other job functions of an examiner.  Stating it evaluates the overall performance may be a slight exaggeration depending on the job functions of the examiners in your office.

Answer b:  The CTS latent print test doesn’t only insure that conclusions are accurate, the conclusions that are considered correct are both accurate (ground truth) and conclusions that others would arrive at (consensus answer).

Answer c:  Proficiency tests do help you comply with accreditation but this answer doesn’t answer the question that was asked.

Answers d, e, and f:  These answers are correct but if someone doesn’t individualize a latent print then these tests don’t determine where the problem lies (orienting a latent print, locating potential candidates, individualizing who left the latent print, or perhaps differing tolerance levels).

Answer g:  This may be the best answer for two reasons.  First, some agencies use the CTS tests for individuals while other agencies take the test as a group.  And second, the conclusions that CTS gives are not simply the ground truth answers but the answers that at least 75% of accredited labs arrived at.

#16: Question – Terminology:

(This question would be to a verifier or a supervisor) The results for KL3 indicate that no identification was effected.  Therefore it has been established that my client did not leave this latent print.  Isn’t that true?

Possible Answers:

a)      Yes.

b)      No.

c)      I’m not sure if the original examiner excluded your client or not.

Discussion:

ASCLD/LAB and SWGFAST both recommend technical reviews.  SWGFAST specifically states that The reported results are clear, concise, accurate, and complete.  Phrases such as ‘No Identification Effected’ may have different meanings to different people.  If agencies are using their own phrases in their reports then these statements should be defined somewhere.

#17: Question – Error Rates:

What is the error rate for fingerprint individualizations?

Possible Answers:

a)      The error rate of the ACE-V methodology is zero.  All errors found have been caused by practitioners not using the methodology as diligently as they should have.

b)      Some rates have been estimated by using the CTS proficiency tests, the IAI certification tests, studies on bias, and errors in training classes.  These estimates may be artificially high because of the parameters of the data for each event.  Empirical data shows the error rate is so extremely low that it’s almost zero.

c)      Our office has standards and controls in place and the error rate of our office is zero. 

d)     In the last 100 years of using fingerprints as a form of identification, between 20 and 30 errors have been found world wide.  When compared to how many comparisons have been done and how many identifications have been made, statistically, the error rate is very close to zero.

Discussion:

One important aspect of this question is that it’s asking for the error rate of individualizations.  If the questions were about fingerprint comparisons then the answers may be very different (we’d have to consider type 1 errors, type 2 errors, errors after the ACE process, errors after the ACE-V process, errors of simple conclusions, errors in complex conclusions, etc).

Answer a:  This is a common answer but it may not be the best answer.  There’s never been any research to support this answer.  Without asking examiners how they arrived at a conclusion, it’s impossible to blame an error on their improper use of ACE-V.  Out of all the errors ever found, the Mayfield erroneous individualization has been the only error researched and had the results published.  While it’s easy to blame errors on examiners, it could be just as easy to blame the agency for not having proper procedures in place.  Besides blaming the examiners involved or the agency, others claim the Mayfield error was due to the extreme similarity between the latent print and Mayfield’s known print.  We may never know the true cause of an error but we can state that errors are very rare.  They may not be zero but they are very close to zero.

Answer b:  This is a good answer because it not only talks about the actual error rate but it acknowledges theoretical error rates that have been published.

Answer c:  Judges have accepted the error rate of an agency since an exact error rate of our profession hasn’t been established.

Answer d:  Even though an exact error rate hasn’t been established, an estimated value is usually acceptable as long you state how the value was determined.

#18: Question – Reliability Studies:

Have there been any reliability studies on ACE-V?

Possible Answers:

a)      I’m not aware of any studies that are published.

b)      There are a number of error rate studies such as…..

c)      There are a number of statistical studies on the probability of two prints having the same characteristics.  Some of the more well known studies are those done by Galton, Balthazard, Cummins, Wilder, Champod, etc.

d)     I know that different people are studying the validity of ACE-V but I’m not sure if any of these studies have been published yet.

e)      Are you speaking about the reliability of the conclusion or the reliability of the method itself (the principles within ACE-V)?  The reliability of a conclusion may sounds impressive but it may not mean you have a good conclusion.  Reliable conclusions just show reproducible results but it doesn’t show if the results are good.  For example, my blender goes the same speed on every setting.  This isn’t good but it happens all the time….it’s very reliable.

f)       Specifically what kind of reliability studies are you looking for?

g)      ACE-V is synonymous with the scientific method of hypothesis testing.  Hypothesis Testing has been used and tested for hundreds of years and found to produce reliable results.

Discussion:

This is an interesting question because it implies that we should have some reliability studies.  If someone answers that none have been done then it looks like we’re using a method that hasn’t been tested.  My experience has taught me that most people asking this question don’t really know what they are looking for.  They are commonly using words that they don’t understand.  For example, reliability indicates that something is able to be reproduced.  It doesn’t indicate that the results are good results.  My toaster is a very reliable instrument; it burns the toast every time I use it.  I can try it over and over again and it always gives the same results.  I can rely on the results my toaster gives even though those are not my desired results. 

When we are asked about reliability tests in court we should ask exactly what are they referring to.

Answer a:  This may be accurate but it implies that ACE-V hasn’t been tested as a viable method and it leave the jury and the court with the opinion that ACE-V isn’t a good way to arrive at conclusions.

Answer b:  This answer assumes the question is about the reliability of our conclusions and this may not be what they are asking about. 

Answer c:  This answer is assuming that they are asking about the possibility of patterns duplicating and it ignores the error rate of our interpretations.

Answers d, e, and f:  These are all good answers but answer e might be giving them more information than they are looking for.

Answer g:  This may be true but it doesn’t answer the question, it just states that ACE-V is accepted but doesn’t show that it’s been tested.

My personal opinion is that d and f are the best answers because they don’t assume the meaning behind the question.

#19: Question – Scientific Basis:

How do you know that fingerprints are unique and permanent?

Possible Answers:

a)      The FBI has been keeping records since the early 1900’s and no two fingerprints have ever found to be the same.  There are also hundreds of thousands of records showing that fingerprints of individuals remain the same.

b)      Several statistical studies have been done to show the possibility of duplication is virtually impossible.

c)      By looking at how the ridge configurations are initially formed. Generally speaking, the interpretation of ridge configurations can be grouped into two categories. The first considers ridge configurations or patterns to be “primary foci of evolution” and therefore directly determined by genetic factors. The second interpretation, proposed by Cummins in 1926, considers ridge configuration as a product of epigenetic processes involving response to growth forces. This second interpretation suggests that ridge configuration is not directly determined by genes but rather is indirectly determined by adjacent tissues with which the developing glandular folds of the basal epidermal layer interact. These adjacent interactive tissues may include the volar skin itself, the soft tissue of the dermis, bone, and/or other epidermal appendages like the fingernails.

d)     Several researchers have done embryonic studies of friction ridge growth and it’s been determined that friction skin patterns are formed by pressures present during the growth process.  Since it’s impossible to duplicate the pressures on any finger or any person, no two fingerprints will ever be the same.  The friction ridges stop forming during a certain time during fetal growth.  Once the growth process stops the friction ridge arrangement is persistent until death and decomposition.

Discussion:

Answer a:  Although this answer is a correct statement, this is empirical evidence.  It shows what we’ve seen to be true but it doesn’t tell us why this event happens (it supports the scientific law but doesn’t give enough data to establish a scientific theory).

Answer b:  The statistical studies done also support uniqueness but they don’t show why it’s impossible for fingerprint arrangements to ever be duplicated.

Answer c:  It’s important to use explanations your audience can understand.  This answer may be adequate for those in our discipline but it may be too much for a jury (an explanation quoted by W. Babler).  Once jurors tune out what you’re saying, it may be very difficult to ever get them back. Be careful not to talk above the jurors level and be careful not to make something so simple that it appears that you’re talking down to them.

Answer d:  This answer doesn’t mention the particulars of the friction ridge growth process but it does give accurate information that’s easy for a jury to understand.  Answers a and b support the scientific theories established by research scientists but this answers states the research done to establish the scientific theories.

#20: Question – Analysis in court:
Will you look at this lift card and tell me what you see?

Possible Answers:

a) (Using a magnifier) I see a whorl pattern latent print that appears to have been processed with black powder.

b) (Using a magnifier) I see friction ridges that are very clear, clear enough to see the edges and pores.

c) This is a latent lift card. On one side it says it’s from case number…..and on the other side is a tape lift. I cannot analyze what’s on the tape here in court; I need the appropriate tools, lighting, and the appropriate amount of time to do an accurate analysis.

Discussion:
It’s a standard policy in some agencies to bring a magnifier to court to analyze latent or known prints. Just because this is a routine procedure doesn’t mean that this is a good procedure. This can be dangerous for a variety of reasons. Problems include using inappropriate equipment, pressures placed on the examiner, no written report or documentation of the results, no verification available, and there’s a tendency to make quick judgments instead of doing a thorough analysis. Examiners should be called to court to testify to the results of previous work completed, not called to court to do additional work on a case. In my opinion, answer c is the only good answer.

#21: Question – Contemporaneous Documentation:
When did this person become a suspect?
When did you do that particular comparison?
How long did it take?

Possible Answers:
a) I’m not sure.
b) I didn’t document that information.
c) It took a while.
d) We don’t document that information because it’s not important to the identification process. Individualizations are based on the characteristics in the images, not on when information was obtained. That may be important to a different part of this case and if it is, then maybe the detective may have that information.
e) (You may be able to give this information if it’s in your case notes).

Discussion:
Contemporaneous documentation of events is important to physical examinations or tasks that can’t be redone at a later date but this isn’t needed or scientifically recommended for analytical tasks, like the identification process, that can be redone at any time.
Answers a and b: People use to recommend short answers but this view isn’t as acceptable as it use to be. If you answer the above question with a short answer then it appears that you did a less than acceptable job….that your work was lacking.
Answer c: If you don’t have the answer then it’s better to say that and indicate why you may not have the answer. Sometimes vague answers, like “it took a while”, appear unprofessional and may give the jury a poor perception of you as an expert.
Answer d: This answer is the same as a and b but it includes the reason why you didn’t do something.
Answer e: If this information is part of your case notes then you can state the answer but it may be important to mention this isn’t required information. If another expert testifies in the same case and they don’t have this type of information then you may not want it to appear that they should have included this information.

#22: Question – Blind Verification – Expected Results:
What happens if the results of blind verification are not the same as the original conclusion?

Possible Answers:
a) If the results are not the same then the individualization isn’t considered a good conclusion.
b) As long as the conclusions aren’t conflicting then there’s not a problem.
c) Conclusions may be different because of differing tolerance levels. One person may make an identification that another person is uncomfortable with due their differing tolerance levels. This is why differing conclusions isn’t a problem.
d) Our agency policy is….(state your agency policy).
e) The conclusions of blind verification are one aspect we assess but another important element to look at is how and why the blind verifier arrived at their conclusions (the justification behind the conclusion).

Discussion:
Answers a and b: If the conclusions are not conflicting (one person individualizes an image and another person says inconclusive) then no erroneous conclusion exists but the blind verification didn’t give any information about the reproducibility to the person using this tool. If a certain process is needed then it should be used in a manner that will give the user some result. When no results are given and the user isn’t concerned then they are either uneducated about the process they are using or perhaps they are not using the process as diligently as they should.

Answer c: Conclusions that differ due to tolerance levels are acceptable. This only becomes a problem when people use this as the reason that conclusions differ when there is no data to lead people to this conclusion (such as no notes that state that consistency existed but not sufficiency). If one person individualizes a latent print and another doesn’t, then we shouldn’t assume that tolerance levels were the issue unless it’s stated. Without this form of documentation, it’s just as likely that the second examiner was unable to correctly orient or locate the area of friction ridge detail that the latent print originated from. It’s also possible that the conclusions were different because different items of evidence were looked at (such as lift cards vs. photographs of lift cards).

Answer d: If your agency has a procedure then stating this it is the best answer. If an agency uses blind verification then it’s advisable to have a procedure which states when and how to use it.

Answer e: If a fingerprint comparison is so complex that blind verification is needed then justification (or documentation of the justification) should accompany the blind verification. Suppose an examiner individualized a latent print to a known print but blind verification resulted in an inconclusive determination. We can’t simple decide that the individualization should or shouldn’t be made; we need to know why this occurred. It’s possible that the two individuals were using different tools (a 4x magnifier vs. computer magnification). It’s possible that the two individuals were using different exemplars (an original vs. a livescan image vs. a copy vs. fax). It’s also possible that the two people have different visual abilities. Some people see certain shades better than others. It’s also possible that one person noticed something in the print that the other person did not. If blind verification resulted in different conclusions then we need to know the justification behind the conclusions and not make a determination about individualization prior to having this information.

#23: Question – Exclusions:
How did you determine the latent print wasn’t made by this person?

Possible Answers:
a) The pattern type wasn’t the same as any of the exemplars from this person.
b) The ridge flow wasn’t the same so I didn’t need to look any further.
c) I looked for a specific target group and this target group didn’t exist in any of the fingers of this person. Then I looked for a second target group as a quality assurance measure.

Discussion:

Answers a and b: Due to the flexibility of the skin, there are times when the ridge flow (level 1detail) appears different but the ridge paths (level 2 details) are consistent. If there’s a sufficient amount of level 2 details then the difference in ridge flow may still be within tolerance for an individualization to be possible. Excluding based on pattern type alone is risky and my result in an erroneous exclusion.

Answer c: This is the best answer because it follows scientific protocols of testing a conclusion prior to arriving at a conclusion.

24: Question – Verification –Exclusions:

Why don’t you verify exclusions?

Possible Answers:

a)      We’ve always done it this way.

b)      That’s our office policy.

c)      We don’t have the manpower to do this.

d)     Erroneous exclusions don’t have the same hazards as erroneous individualizations.  Nobody will be falsely imprisoned due to an erroneous exclusion.  We verify individualizations as a quality assurance measure.  This measure isn’t needed for exclusions. 

e)      If the examiner is competent and they say it’s not an ID then it’s not an ID.

f)       We don’t exclude people from leaving a latent print.  Our agency either individualizes a latent print or states that no individualization was effected.

g)      Our agency verifies all conclusions.

Discussion:

Answers a and b:  “We’ve always done it this way” and “It’s our office policy” is never a good answer.  People should know why policies exist and be able to communicate the reasons to other people.

Answer c:  A lack of manpower is never an adequate reason for not doing something that should be done.  This sounds more like an excuse than a valid reason.  Another topic for discussion regarding this answer is the use of the term ‘ID’ vs using the term ‘individualization’ (but that’s a topic for another discussion).

Answer d:  This is a valid reason for not verifying exclusions but examiners should remember that erroneous exclusions can have serious effects.  If someone is erroneously excluded from leaving a latent print then this may leave a guilty person in the community to commit more crimes.

Answer e:  This sounds reasonable but agencies that verify all conclusions know that even competent examiners may not be able to orient or locate all latent prints.  The accuracy of a conclusion is in the justification behind the conclusion and not in the competence of the examiner.

Answers f and g:  If either of these answers are your office policy then I see nothing wrong with these answers.

#25: Question – Accreditation:

Are you accredited?

Possible Answers:

a)      No

b)      Yes, by ASCLD

c)      Yes, by ASCLD/LAB

d)     Yes, we’re accredited by the International Organization for Standardization (ISO)

e)      Yes, we’re accredited by International Standards Organization (ISO)

Discussion:

Using acronyms is always discouraged because the people you’re trying to educate (the courts) don’t know what these acronyms stand for.

Answer a:  Stating that your lab isn’t accredited may be the correct answer but it leaves the courts feeling like you aren’t meeting the responsibilities that you should be meeting.  If your lab isn’t accredited but you feel that it is meeting the responsibilities that it should then perhaps you could say, “No, my lab isn’t accredited but we do have quality assurance measure in place and we follow the guidelines set by SWGFAST (The Scientific Working Group for Friction Ridge Analysis, Study, and Technology)”.

Answers b and c: ASCLD/LAB is one of the organizations that offer accreditation to agencies.  If you are accredited by ASCLD/LAB you should use the complete name in court, American Society of Crime Laboratory Directors / Laboratory Accreditation Board.  Forensic Quality Services (FQS) is another company that accredits forensic laboratories.  It should be noted that ASCLD is different than ASCLD/LAB.  ASCLD does not accredit agencies.

Answers d:  ASCLD/LAB has two accreditation programs, Legacy and International. The ASCLD/LAB International program and the FQS program both adhere to the ISO standards, but ISO doesn’t directly accredit laboratories. 

Answer e: ISO stands for International Organization for Standardization.  Stating the wrong words for an acronym will lower the value of your entire testimony.

#26: Question – Terminology – Permanence or Persistence:

Can you please describe fingerprint permanence to the court.

Possible Answers:

a)      The friction ridge arrangements on the skin are formed during fetal formation and remain the same until after death and decomposition starts.

b)      The friction ridge arrangements on the skin are formed during fetal formation and are permanent until after death and decomposition starts.

c)      The friction ridge arrangements on the skin are formed during fetal formation and are persistent until after death and decomposition starts.  Persistent means that they do change in size and can be different due to the flexibility of the skin but the characteristics themselves do not change.

#27: Question – Error Rate of the Methodology:

What is the error rate for the ACE-V methodology?

Possible Answers:

a)      The error rate of the ACE-V methodology is zero.

b)      You can’t divide the error rate between the methodology and the practitioner because you can’t use the method without a human being.

c)      You can separate the practitioner error rate from the error rate of the methodology but these wouldn’t be actual error rates, they’d be theoretical error rates.

d)     I’m not aware of any research studies that have calculated an error rate for the methodology but the known errors over the last 100 years are extremely small (between 20 and 30 out of billions of comparisons).          

e)      I’m not aware of any research studies that have calculated an error rate for the methodology.  If this were to be done then there would be several error rates, 1 for type 1 errors, a rate for type 2 errors, a rate for clerical errors, a rate for the profession, a rate for an agency, and another rate for an individual.

f)       If you look at ACE-V as being synonymous with hypothesis testing then you can’t have an error rate because ACE-V isn’t a specific method, it’s more of a general guideline.  Error rates can only be calculated for detailed techniques.  Our profession doesn’t have an error rate for ACE-V but our overall error rate is known to be extremely low.

Discussion:

Answer a:  This is a common answer but it may not be the best answer.  There’s never been any research to support this answer.  If you use this answer, it’s very likely that the next question will be, “how did you arrive at this number”? 

Answer b:  This is another common answer but not very accurate.  Using any technique, method, or tool needs human intervention but other sciences manage to calculate the error rate of the tool and the error rate when a human uses the tool.  These error rates are commonly known as theoretical error rates and actual error rates. 

Answer c:  The error rate of a tool, independent of the practitioner, is known as a theoretical error rate.  The error rate of the tool being used by a human is usually higher than the theoretical error rate.

Answer d:  Judges have accepted this since it’s an estimate arrived at by using empirical data.

Answer e:  This may be an accurate answer but it’s a little more than what was asked for.  Sometimes if you give too much information then you lose the attention of the jurors.  Once you lose the juries interest, it’s very hard to get it back.

Answer f:  Daubert doesn’t require that we know the error rate of the method, just an error rate in applying the method.  This answer is good because it brings the conversation back to a more relevant topic.

#28: Question – The FBI - Lockheed Martin 50k x 50k Study:

Any question regarding the FBI - Lockheed Martin 50k x 50k Study.

Possible Answers:

a)      This was a research study done in 1999 to show support for the theory of biological uniqueness of fingerprints.

b)      This was a study that showed the probability of the same configuration of minutia occurring in two fully rolled prints is 1 in 10 to the 97^th power.  The probability of a latent print having the same minutia as another rolled impression is 1 in 10 to the 27^th power.

c)      This was a study done in 1999 by the FBI and Lockheed Martin.  This study has never been published or peer reviewed to show if the study or the results are scientifically sound.  Until this is done it would be improper for me to testify to this study.

Discussion:

How you chose to testify is your choice but even if you have in-depth information regarding this study, it may not be scientifically valid since it hasn’t been peer reviewed.  Giving the jury information you know isn’t supported, isn’t educating the jury but it’s a sign that you’re trying to convince the jury of your view.  This is a sign that an expert witness isn’t independent or objective in their views and some people may consider this to be an inappropriate action.

#29: Question – Science or Technology:

Are fingerprint comparisons a science or a technical endeavor?

Possible Answers:

a)      It’s a science.

b)      It’s a technical endeavor.

c)      Conclusions can be arrived at in a variety of ways but my conclusions are done scientifically.

d)     There are differing opinions on this.  Some people think it’s a science and other people say it’s a technical endeavor.  I believe……..because…….

Discussion:

Whatever answer you choose, it’s important that you’re able to back up your answer.  To do this you must be able to state the difference between a scientific endeavor and a technical endeavor.  There is no simple list of what constitutes a scientific endeavor.  Hundreds (if not thousands) of books have been written on the subject and some people even claim that the definition is evolving all the time.  This may be true but there are some very basic qualifications for something to be considered a scientific endeavor.  Usually science refers to natural phenomenon.  Scientific endeavors need to use accepted principles to arrive at the conclusion, be reproducible by others, open for others to review or scrutinize, testable, and conclusions are considered to be the best possible conclusions given the available data.  These conclusions are seldom absolute and final but they are conclusions that have gain acceptability.  Science always leaves the door open for better conclusions.  Science recognizes subjectivity and bias and tries to account for these types of things.  Science doesn’t require contemporaneous documentation, analytical documentation, complete objectivity, statistical probabilities, blind verification, or confirmation of the results. But it does recognize the benefits of all of these different tools.  Science doesn’t require a degree, anyone who appropriately uses scientific protocols can perform scientific endeavors.

Answers a and b:  Either of these answers could be true but they don’t have the weight behind them that an answer with an explanation has.

Answers c and d:  These answers sound good because they don’t give out too much information but it does sound like the practitioners can justify their conclusions and are prepared to do so.