In Maryland, firearms experts will no longer be allowed to testify that a specific gun fired a specific bullet, the state’s highest court ruled in an opinion published Tuesday.

Ref:

https://www.baltimoresun.com/n...+link+guns+to+crimes

I think this is a big deal. Opinions, please.

Article is behind a paywall. I've always been more skeptical of DNA science but felt ballistics science was more on solid ground. Still mistakes and manipulation can and does happen in all these labs.

Unable to read the article, hidden behind a paywall.

Funny thing is I always thought the opposite. DNA seems pretty clear cut, ballistic stuff seemed like bullshit. 2 barrels made on same day, side by side, and I am supposed to believe the gouges it makes in a lead bullet traveling the speed of sound are legit. Sounded hokey as all get out. It always seemed more likely to say a bullet didn't come out of THIS gun but not an exact gun, ie exclude a gun but not ID one. Never did a deep dive though so I certainly don't know shit. Funny thing is Maryland was one of those states that for years kept the shell casings because they "thought" they could solve a crime with that as well. lol

Without being an expert in the field, I've always thought a more accurate term would be, more likely than not from a particular gun.
Saying every match has the same million to one, or whatever number is quoted, odds seems speculative to some degree.
Similar to a circumstantial case that has to have enough other evidence so a jury or judge can decide for themselves what's likely true.
Having the shell casings from a scene and the tested weapon to compare would help to confirm as that's another variable.

Opened right up for me using Firefox ESR (w/ AdGuard AdBlocker)

Maryland Supreme Court imposes limits on ballistics evidence used to link guns to crimes

By Alex Mann - Baltimore Sun
Jun 21, 2023 at 10:07 am

In Maryland, firearms experts will no longer be allowed to testify that a specific gun fired a specific bullet, the state’s highest court ruled in an opinion published Tuesday.

Authored by Chief Justice Matthew J. Fader of the Supreme Court of Maryland, the opinion imposes limits in the courtroom on the practice known as firearm “tool mark” analysis. The forensic technique postulates that machines used to make guns leave tiny imperfections on their components, and that those components imprint unique marks on ammunition — composed of softer metal — when fired.

Until now, it was commonplace for firearms examiners — usually employed in police crime labs — to testify that a gun recovered by law enforcement fired bullets or casings found at a crime scene, if they believed that to be true based on their observations under a microscope.

[ Under the microscope: Maryland high court considers limiting ballistics evidence used to link guns to shootings ]

But four of seven justices on the state Supreme Court found that the scientific methodology is not reliable enough to allow examiners to testify that a particular gun fired a particular bullet. Examiners can, however, testify “that patterns and markings on bullets are consistent or inconsistent with those on bullets fired from a particular known firearm,” the opinion said.

The ruling responds to the appeal of a murder case in Prince George’s County, but all decisions by the state’s highest court are binding on lower courts.

One of the attorneys behind the appeal, Stanley Reed, described the legal team as “very gratified.”

The Maryland Office of the Attorney General, which represented the state in the appeal, did not immediately respond to a request for comment Tuesday evening.

With the opinion, Maryland becomes one of the first jurisdictions in the country where an appellate court has recognized shortcomings in the forensic practice and imposed limits on its use in court, according to experts.

Maneka Sinha, an associate professor at the University of Maryland Francis King Carey School of Law who studies forensic sciences, said the justices “came to the conclusion that scientists, academics and others seriously studying the discipline already have: that conclusions claiming they can say a specific gun fired a specific item of ammunition are simply unreliable.”

“These kinds of unreliable conclusions have been central to prosecutors securing countless convictions — convictions we should all be questioning now,” added Sinha, who successfully argued for one of the first limits placed on firearm analysis testimony in a case from the Superior Court of the District of Columbia cited in the Maryland appeal.

Jeffrey Gilleran, chief of the forensics division at the Maryland Office of the Public Defender, echoed Sinha’s comments.

“For too long has the criminal legal system allowed unvalidated and unreliable methods to be admitted at trial,” Gilleran said in an email. “This opinion is a step in the right direction and we look forward to this type of in-depth analysis for other forensic disciplines, even those that have long been considered settled.”

When there is a shooting, police typically cordon off the area with crime scene tape. Crime lab technicians respond to mark evidence, photograph it and collect it. Then, they take it back to the crime lab for further testing. Key among that evidence is usually fired cartridge casings.

A casing encapsulates a bullet. After a trigger is pulled, a firing pin rams the back of the casing, which ignites an explosive substance inside. That propels the bullet down a barrel, which features twisted metal known as “rifling” inside, to spin the projectile for accuracy. A semiautomatic handgun ejects a casing after each shot.

If a gun is recovered during an investigation, firearms examiners test-fire the gun. Then they use comparison microscopes, which allow them to look at two pieces of evidence simultaneously, to compare bullets or casings picked up at the crime scene with those from the test fires. They then decide whether they believe there are enough markings on the spent projectiles to declare a match.

The Association of Firearm and Tool Mark Examiners says examiners can declare a match when an examiner sees “sufficient agreement” between two projectiles. The organization, which establishes standards for the field, says agreement between two rounds is significant when a set of markings is of “a quantity and quality that the likelihood another tool could have made the mark is so remote as to be considered a practical impossibility.”

There are five conclusions an examiner can reach: elimination of a bullet as having been fired from a specific gun, identification of a projectile being fired by that gun and “inconclusive.” There are three types of inconclusive findings an examiner can cite: one that leans toward excluding a match, one that leans toward a match and one that represents greater uncertainty.

Proponents of the practice say that firearms examiners rarely declare a match incorrectly.

But how often examiners’ findings are wrong is a subject of great dispute. Lawyers on either side of the appeal pointed to studies with error rates ranging from zero to 50%.

That discrepancy likely has to do with how “inconclusive” findings are counted. Critics say that most firearm analysis studies count inconclusive as correct, artificially deflating the error rate.

One of the three dissenting justices, Steven B. Gould, wrote that the court shouldn’t worry about inconclusive findings.

“Our concern is this: when the examiner does declare an identification or elimination, we want to know how reliable that determination is,” Gould said in his dissenting opinion. “The record shows that conclusive determinations of either kind (identification or elimination) are highly reliable.”

quote:

Funny thing is I always thought the opposite. DNA seems pretty clear cut, ballistic stuff seemed like bullshit. 2 barrels made on same day, side by side,

Me too!

I had my dog's DNA tested. Twice.
Based on the results given to me I have absolutely NO trust in DNA science.

If I was serving on a jury I would disregard any so called "evidence" based on DNA.

Didn't Maryland try to establish an expensive ballistic database that never worked?

Or was that Canada?

quote:

Originally posted by Sigmund:
Didn't Maryland try to establish an expensive ballistic database that never worked?

Or was that Canada?

Both.

As a career machinist I just can't buy the notion of ballistics matching. I'm going to need to see ten barrels rifled consecutively, and multiple slugs from each to sway my skepticism. Barrels made by the same tooling, on the same day, and one or two pieces apart in order, and all that.

Moreover, when I see these crime shows on TV, (documentary type) they show the two slugs side by side, my eye usually picks up subtle differences between the alleged "matching" slugs.

Show me two slugs purported to be a match, I'd bet there's at least some spot on them where they don't.

I'm just saying they're not fingerprint evidence, in my judgment.

The day a defense attorney presents matching ballistics, and introduces evidence they came from two different guns a couple of serial numbers apart this whole thing throws a lot of cases into doubt.

It seems to take a lot on faith. A prosecutor would surely not want me on the jury eyeballing ballistics.

So, obviously we need to require micro engraving on firing pins, you know "for the children."

The specific gun stuff has been rejected for a long time, TMK - identifying a particular make is fairly common.

No reason at all to doubt DNA evidence, if the lab is legitimate.

Trying to identify dog breeds could be complex - breeds are highly inbred and there’s going to be very subtle genetic differences between them (which is why they can interbreed).

Lots of work in identifying a particular human/human parentage/humans are not inbred, for the most part, so there’s more stuff to look at.

quote:

Originally posted by lastmanstanding:
Article is behind a paywall. I've always been more skeptical of DNA science but felt ballistics science was more on solid ground. Still mistakes and manipulation can and does happen in all these labs.

The problem with "ballistics science" is that it has not been subjected to really rigorous scientific verification, as I understand it. As in: there aren't double-blind tests to see if examiners can actually accurately determine whether a given bullet came from a given gun, or even some lesser claim. The "science" is more observational, and has not been tested rigorously.

I have certainly heard ballistics experts say, when they have no skin in the game, that there is a fair degree of subjectivity and room for error as well.

I have long had a belief that proponents of this "science" were overstating how reliable and accurate it is.

I have often wondered just how reliable bullet matching was. I'm sure it is useful, but doubtful that it can rule out a particular gun.

flashguy

It always sounded like something created for a script in Hollywood than it was in reality....

I totally agree with the decision. I have said for years that with modern machines there is going to be very little difference. I worked in Quality assurance for 25 years and also machining .
About the only thing they might be able to prove is brand of firearm