Ballistics experts can’t testify that recovered bullets match firearms, Md. high court rules

dobedo

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https://thedailyrecord.com/2023/06/...d-bullets-match-firearms-md-high-court-rules/

The decision could make a difference in cases where a defense lawyer objected to the evidence and an appeal is still possible, said appellate lawyer Steven M. Klepper, who was not involved in the case.

Prior convictions that were based on firearms identification evidence won’t automatically be reopened because of this ruling, but defendants could file a petition for a writ of actual innocence, Klepper said.
 
I bet a lot of MD defense attorney are preparing documents.documents to appeal the cases of past and present clients. It will be interesting to see if the decision spins off into other states.
 
Here in Legal, we don't generally allow threads to run based on news stories. That said, does anyone have a link to the actual decision? We need to see the actual language. The thought that occurs to me is that there's a big difference between a firearms examiner testifying that "Bullet A came from Defendant's Glock 19, serial # 12345," and "the rifling marks on the recovered round are consistent with Defendant's Glock 19, serial #12345."
 
does anyone have a link to the actual decision? We need to see the actual language.
Here you go - https://mdcourts.gov/data/opinions/coa/2023/10a22.pdf

SUPREME COURT OF MARYLAND
KOBINA EBO ABRUQUAH v. STATE OF MARYLAND
Filed: June 20, 2023

Firearms identification, a subset of toolmark identification, is “the practice of investigating whether a bullet, cartridge case or other ammunition component or fragment can be traced to a particular suspect weapon.” Fleming v. State, 194 Md. App. 76, 100-01 (2010). The basic idea is that (1) features unique to the interior of any particular firearm leave unique, microscopic patterns and marks on bullets and cartridge cases that are fired from that firearm, and so (2) by comparing patterns and marks left on bullets and cartridge cases found at a crime scene (“unknown samples”) to marks left on bullets and cartridge cases fired from a known firearm (“known samples”), firearms examiners can determine whether the unknown samples were or were not fired from the known firearm.

At the trial of the petitioner, Kobina Ebo Abruquah, the Circuit Court for Prince George’s County permitted a firearms examiner to testify, without qualification, that bullets left at a murder scene were fired from a gun that Mr. Abruquah had acknowledged was his. Based on reports, studies, and testimony calling into question the reliability of firearms identification analysis, Mr. Abruquah contends that the circuit court abused its discretion in permitting the firearms examiner’s testimony. The State, relying on different studies and testimony, contends that the examiner’s opinion was properly admitted.

Applying the analysis required by Rochkind v. Stevenson, 471 Md. 1 (2020), we conclude that the examiner should not have been permitted to offer an unqualified opinion that the crime scene bullets were fired from Mr. Abruquah’s gun. The reports, studies, and testimony presented to the circuit court demonstrate that the firearms identification methodology employed in this case can support reliable conclusions that patterns and markings on bullets are consistent or inconsistent with those on bullets fired from a 2 particular firearm. Those reports, studies, and testimony do not, however, demonstrate that that methodology can reliably support an unqualified conclusion that such bullets were fired from a particular firearm.

The State also contends that any error in the circuit court’s admission of the examiner’s testimony was harmless. Because we are not convinced “beyond a reasonable doubt, that the error in no way influenced the verdict,” Dionas v. State, 436 Md. 97, 108 (2013) (quoting Dorsey v. State, 276 Md. 638, 659 (1976)), we must reverse and remand for a new trial.

(Page 55)

J. Relationship Between Reliability of Methodology and Opinion to Be Offered

Based on the State’s evidence concerning the reliability of firearms examinations and “a dearth of real-life examples of erroneous examinations,” the circuit court concluded that “firearm and toolmark evidence is known to reach reliable results” and, therefore, that this final factor favors admission of the evidence. We do not question that firearms identification is generally reliable, and can be helpful to a jury, in identifying whether patterns and markings on “unknown” bullets or cartridges are consistent or inconsistent with those on bullets or cartridges known to have been fired from a particular firearm. For that reason, to the extent Mr. Abruquah suggests that testimony about the consistency of such patterns and markings should be excluded, we disagree.31 It is also possible that experts who are asked the right questions or have the benefit of additional studies and data may be able to offer opinions that drill down further on the level of consistency exhibited by samples or the likelihood that two bullets or cartridges fired from different firearms might exhibit such consistency. However, based on the record here, and particularly the lack of evidence that study results are reflective of actual casework, firearms identification has not been shown to reach reliable results linking a particular unknown bullet to a particular known firearm.

For those reasons, we conclude that the methodology of firearms identification presented to the circuit court did not provide a reliable basis for Mr. McVeigh’s unqualified opinion that four bullets and one bullet fragment found at the crime scene in this case were fired from Mr. Abruquah’s Taurus revolver. In effect, there was an analytical gap between the type of opinion firearms identification can reliably support and the opinion Mr. McVeigh offered.32 Accordingly, the circuit court abused its discretion in permitting Mr. McVeigh to offer that opinion.

(Page 57)

IV. HARMLESS ERROR

The State argues in the alternative that any error in admitting Mr. McVeigh’s testimony was harmless. We disagree.

... Upon our review of the record, we are not convinced beyond a reasonable doubt that the expert testimony in no way contributed to the guilty verdict. The firearm and toolmark identification evidence was the only direct evidence before the jury linking Mr. Abruquah’s gun to the crime. Absent that evidence, the guilty verdict rested upon circumstantial evidence of a dispute between the men, a witness who heard gunfire around the time of the dispute, a firearm recovered from the residence, and testimony of a jailhouse informant. To be sure, that evidence is strong. But the burden of showing that an error was harmless is high and we cannot say, beyond a reasonable doubt, that the admission of the particular expert testimony at issue did not influence or contribute to the jury’s decision to convict Mr. Abruquah. See Clemons v. State, 392 Md. 339, 372 (2006) (stating that “[l]ay jurors tend to give considerable weight to ‘scientific’ evidence when presented by ‘experts’ with impressive credentials” (quoting Reed v. State, 283 Md. 374, 386 (1978))).

CONCLUSION

Based on the evidence presented at the hearings, we hold that the circuit court did not abuse its discretion in ruling that Mr. McVeigh could testify about firearms identification generally, his examination of the bullets and bullet fragments found at the crime scene, his comparison of that evidence to bullets known to have been fired from Mr. Abruquah’s Taurus revolver, and whether the patterns and markings on the crime scene bullets are consistent or inconsistent with the patterns and markings on the known bullets. However, the circuit court should not have permitted the State’s expert witness to opine without qualification that the crime scene bullets were fired from Mr. Abruquah’s firearm. Because the court’s error was not harmless beyond a reasonable doubt, we will therefore reverse the circuit court’s ruling on Mr. Abruquah’s motion in limine, vacate Mr. Abruquah’s convictions, and remand for a new trial.​
 
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That's fairly reasonable, IMO. They aren't saying the forensics evidence isn't admissible, only that it's unacceptable for the expert to testify that no other gun could have possibly fired the bullets. There is a small, but non-zero probability that some other gun could have the same characteristics needed to mark the bullet so that it appeared to come from the defendant's gun. The expert needs to address that possibility constructively instead of totally dismissing it.

Note that the defendant isn't getting off scott free, he will be retried. It seems likely that if this ruling affects other cases, a similar outcome would be the result--a retrial.
 
This is something I've been curious about for a while. This type of matching is often portrayed as 100% accurate, which anyone who's ever tested anything knows can't be true. Hopefully this case will shed some light on how reliable it really is, or at least can be. People can mess up anything.
 
That's fairly reasonable, IMO. They aren't saying the forensics evidence isn't admissible, only that it's unacceptable for the expert to testify that no other gun could have possibly fired the bullets. There is a small, but non-zero probability that some other gun could have the same characteristics needed to mark the bullet so that it appeared to come from the defendant's gun. The expert needs to address that possibility constructively instead of totally dismissing it.

Note that the defendant isn't getting off scott free, he will be retried. It seems likely that if this ruling affects other cases, a similar outcome would be the result--a retrial.

This is actually something of an emerging issue in forensic evidence.

For a number of years I've attended a program on forensic evidence put on annually by the National Association of Criminal Defense Lawyers, and this has been frequently discussed. While it may be relatively straight forward to establish that a particular effect (e. g., markings on a fired bullet, tool marks on a pried open door, etc.) was caused by a particular device, it's not necessarily clear how many other, similar devices could have caused a matching result.
 
The decision is a remarkable one. The description of the issue, the statements regarding the rule, the application, and analysis--particularly the analysis--and the conclusion are set forth with thoroughness, very clearly.

As it happens, Maryland switched from the Frye rules of evidence to Daubert fairly recently.

I took a course in evidence law earlier this year, and the instructor opined that toolmark analysis in firearms identification is junk science.
 
I am not an expert on this type of stuff, but I think we can say that evidence is evidence, but not all evidence is conclusive.

It becomes obvious that when a crime bullet matches the markings of a test bullet, this supports the likelihood that the test gun fired the crime bullet, but does not prove it.

I would also expect that the probability that there is another gun in the area that would also match the crime bullet can be estimated to some extent. I would think that the probability of a "plausible alternate gun" on a Glock 9mm in Dallas (high volume gun, high gun density area, possibly less distinctive markings) is more than when the gun is an 8mm Nambu in a remote location small town.

If the police find what looks to be an exact match between ammo found with the gun and a crime bullet, this would seem to have the potential to make their case much stronger.
 
It becomes obvious that when a crime bullet matches the markings of a test bullet, this supports the likelihood that the test gun fired the crime bullet, but does not prove it.
The issue is one of how closely it matched.

I would also expect that the probability that there is another gun in the area that would also match the crime bullet can be estimated to some extent
That is indeterminable.

If the police find what looks to be an exact match between ammo found with the gun and a crime bullet, this would seem to have the potential to make their case much stronger.
"looks to be...exact" means nothing.

Tool mark analysis can prove that a particular gun was not the one that was used, and it can prove that it might be the one that was used--and that's it.
 
It seems to me that this is a case where the firearms examiner maybe made a stronger case that the firearm in question was what fired the bullet than was warranted.

I am curious how they could retry it and have him come back in and claim that his original testimony was in error, so that rather than there is no question about what firearm fired the bullet in question, it is more like a high degree of probability.
 
It seems to me that this is a case where the firearms examiner maybe made a stronger case that the firearm in question was what fired the bullet than was warranted.
Exactly.
I am curious how they could retry it and have him come back in and claim that his original testimony was in error, so that rather than there is no question about what firearm fired the bullet in question, it is more like a high degree of probability.
The examiner may not testify regarding probability. He can only testify that the markings on the subject bullet are consistent with those that that gun would have made.
 
The ruling does not prevent an examiner from testifying regarding probability. His assessment of probability/opinions about probability would be subject to refutation/attack by the other side's experts.

Same as his assessment that the markings are consistent with the defendant's gun. The other side can attempt to refute/attack that assessment with their own experts.
 
The ruling does not prevent an examiner from testifying regarding probability.
According to Attorneys Andrew Branca and Mike Gosney, the ruling prohibits expert witnesses from offering opinions regarding the likelihood that a bullet or case is a match.

The reason is the same as that for prohibiting an expert opinion that the specimen is a match: there are no data that would provide a scientific basis for such an opinion.

Basic Daubert and FRE stuff.

Prediction: the same arguments may well prevent experts from testifying about probable distances based on gunshot residue patterns. That subject has not yet been subjected to evaluation under Daubert rules.
 
It would be subject to Daubert/Frye rules, but if the expert could provide a repeatable/scientifically based rationale/justification that met the applicable standard (which could, admittedly, be quite difficult) it would be allowed. There's nothing in the ruling that explicitly prohibits testimony about probability.
 
It would be subject to Daubert/Frye rules, but if the expert could provide a repeatable/scientifically based rationale/justification that met the applicable standard (which could, admittedly, be quite difficult) it would be allowed.
That's the issue. If one could do that, the ruling would never have been made.
There's nothing in the ruling that explicitly prohibits testimony about probability.
I think that the words "any level of" in "Nonetheless, the court agreed with Mr. Abruquah that the subjective nature of the matching analysis made it inappropriate for an expert to “testify to any level of practical certainty/impossibility, ballistic certainty, or scientific certainty that a suspect weapon matches certain bullet or casing striations" covers that. In any event, attorneys Branca and Gosney believe that there is no question about it.

Gosney's office has been working on this in real cases for some years, I took a course in the law of evidence that was taught by one of his colleagues earlier this year, and there was a whole module devoted to this subject. He predicted everything about the ruling except the timing and the court.

As one who was deeply immersed in Daubert and the FRE in a prior life, albeit on a different subject, I found this extremely interesting.

The Law of Self Defense blog post on the ruling is worth the not insignificant time and effort required.

BTW, the analysis must also be reproducible--someone else would get the same results. That's one of the major shortcomings in the method that has theretofore been accepted.
 
"Mr. McVeigh could testify ... whether the patterns and markings on the crime scene bullets are consistent or inconsistent with the patterns and markings on the known bullets. However, the circuit court should not have permitted the State’s expert witness to opine without qualification that the crime scene bullets were fired from Mr. Abruquah’s firearm. "

There should be more to the prohibited opinion than the questionable certainty of the bullets having been fired from the defendant's firearm. There is also uncertainty whether the bullets were fired from a particular firearm at a particular time and in a particular place, the "crime scene."
 
If one could do that, the ruling would never have been made.
There's a huge difference between saying: "This gun fired this bullet to the exclusion of all others." (which is not allowed under the ruling) and "The probability that some other gun fired this bullet is X%." which is not forbidden under the ruling.

How one would go about calculating the probability in a manner that would stand up to Daubert/Frye is not exactly clear, but similar calculations are made when using DNA evidence. It would likely be quite difficult to come up with such a method, but if an expert could do so, there is nothing in the ruling that would prevent them from doing it.
I think that the words "any level of" in "Nonetheless, the court agreed with Mr. Abruquah that the subjective nature of the matching analysis made it inappropriate for an expert to “testify to any level of practical certainty/impossibility, ballistic certainty, or scientific certainty that a suspect weapon matches certain bullet or casing striations" covers that.
In each case, the ruling talks about "certainty/impossibility", "certainty" and "certainty". In other words, it is not allowed to say that it is certain that this bullet was fired from this gun or impossible that it was fired from some other gun. That doesn't prohibit an expert from (within the Daubert/Frye framework) providing a probability (which is, all about uncertainty and possibility, not certainty and impossibility) if they can do so. Just as is done with DNA. With DNA, they aren't allowed to say that it was absolutely this person, only to state a probability (or, more typically, a lower bound for the probability).
BTW, the analysis must also be reproducible--someone else would get the same results.
Right, that's Daubert in a nutshell.
 
There's a huge difference between saying: "This gun fired this bullet to the exclusion of all others." (which is not allowed under the ruling) and "The probability that some other gun fired this bullet is X%." which is not forbidden under the ruling.
Please review the LoSD blog post on that question.
similar calculations are made when using DNA evidence.
DNA evidence is condsidred the gold standard in forensics.
it is not allowed to say that it is certain that this bullet was fired from this gun or impossible that it was fired from some other gun. That doesn't prohibit an expert from saying (within the Daubert/Frye framework) from providing a probability if they can do so.
But they cannot, for the reasons discussed in detail in the ruling.
 
here should be more to the prohibited opinion than the questionable certainty of the bullets having been fired from the defendant's firearm. There is also uncertainty whether the bullets were fired from a particular firearm at a particular time and in a particular place, the "crime scene."
Different topic entirely.
 
DNA evidence is condsidred the gold standard in forensics.
And yet, just as in this case, the expert witness is not allowed to testify that a DNA match provides certainty, only that it provides a level of confidence based on probability calculation.
But they cannot, for the reasons discussed in detail in the ruling.
The probability calculation would be difficult and would require a lot of groundwork, but might be possible. Things that would factor in:
  • How many firearms are estimated to be able to fire bullets with the characteristics in question. (Caliber/Weight/Twist/Land&Groove Count/Land&Groove dimensions and characteristics)
  • Based on experimentation, how long will the type of rifling machine used to rifle the barrel of the firearm in question generate a particular pattern of toolmarks in a series of manufactured firearms before the pattern changes perceptibly. This would take a ton of work but is not impossible, just arduous and probably expensive--especially in the beginning.
  • Based on statistical analysis (there's a PHd paper out there that takes a stab at this) of the toolmarks themselves, how likely is it that they could occur randomly in another bore.
Difficult and time-consuming, but, if accomplished properly, repeatable to within some margin of error--which would, of course, be part of the testimony.

In a nutshell, here's the ruling: "However, the circuit court should not have permitted the State’s expert witness to opine without qualification that the crime scene bullets were fired from Mr. Abruquah’s firearm."

Probability is the ultimate method of qualifying a statement.
 
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