Criminal Justice

How Junk Science Sends Innocent People to Jail

It's time to reform our criminal justice system.


On TV crime shows like CSI, NCIS, and Law & Order, science gets the bad guys.

In real life, "science" often ensnares the innocent.

Former NYPD Detective Harry Houck gets annoyed when TV shows make forensic science look infallible.

"You watch a detective get down and look at a body (and say), 'He's been dead for three hours now… (H)e ate dinner four hours ago,'" scoffs Houck. "I can't do that."

On TV, experts identify killers by their bite marks. In real life, experts claimthey can do that.

The TV show Cold Case Files covered the trial of Alfred Swinton. He was convicted of murder because a bite-mark expert said his teeth matched a bite on the victim.

"A perfect match!" said Dr. Gus Karazulas, the "forensic odontologist" whose testimony clinched the conviction.

Karazulas sounded impartial and objective. "A forensic scientist is not on the side of the prosecutor or defense," he said on Cold Case Files. "We look at the evidence."

But Swinton was innocent. Lawyer Chris Fabricant helped get him released from jail by doing a DNA test, a much more reliable, less subjective form of science.

Fabricant scoffs at bite-mark testimony: "The doctor was just wrong. It's an unreliable technique."

The more room there is for an expert witness's unique interpretation of the data, the more that can go wrong, says Fabricant. "Bite mark is similar to you and I looking at a cloud. I say to you, 'John, doesn't that cloud look like a rabbit?' And you say, 'Yeah, Chris, I think that does look like a rabbit.'"

That kind of junk science puts innocent people in jail.

I told Fabricant that I assumed most people in jail are guilty. Also, many people say crime is down because aggressive law enforcement has locked so many people up.

"If you think that maybe even 1 percent of convicted defendants may be innocent," replied Fabricant, "we have 2.6 million people in prison today, (so) we are talking about tens of thousands of (innocent) people!"

Fabricant works with the Innocence Project, a group that works to get innocent people freed from prison. Through DNA evidence, the project's lawyers have helped free 191 people.

That confident bite-mark expert who got Swinton convicted now admits he was wrong. "Bite mark evidence is junk science," he told us via email. He resigned from the American Academy of Forensic Sciences.

But police still trust bite marks.

"Let's say one tooth is missing in the front" of a bite mark, explains Houck. "You've got to go, well, our suspect's got one tooth missing in the front. That's pretty good!"

Houck says he'd demand other evidence. But not all cops do—especially when scientific "experts" say someone's guilty.

Bite marks are just one dubious method police and prosecutors use.

FBI researchers claim fingerprints are right more than 99 percent of the time. But that still leaves plenty of wrongful convictions.

After terrorists killed 193 people in Madrid, the FBI matched a fingerprint on a terrorist's bag to a man in Oregon named Brandon Mayfield. They arrested him. But Mayfield was innocent. Weeks later, Spanish investigators compared the prints more carefully and found the real terrorist.

Other techniques are even less accurate: carpet-fiber evidence, gun tracing, use of psychics, hair matching.

"A dog hair was associated wrongfully with a human hair," says Fabricant. "Since the turn of this century, there have been 75 wrongful convictions (based on hair matches)."

Why do judges and lawyers accept such dubious evidence?

"We all went to law school because we don't know science, we don't know math," he replied. "If somebody comes in in a white lab coat, and says, 'I've been accredited by the American Board of Forensic Odontology,' that's good enough for government work."

That shouldn't be. Too much is at stake.

Jurors tend to believe people who call themselves "scientists."

Judges should be more skeptical. They should ban junk science from courtrooms.

NEXT: Congress Approves 'Right to Try' Bill for Critically Ill

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  1. I would like to think that the “expert” witness would be discredited completely in any legal testimony he makes, and his work to date discredited completely in any legal context.

    OT: Is Reason working on any criticism of the new Netflix + Vox series Explained?

    It looks very much like the huge sack of cynicism, spite, selective and highly subjective “fact”, and outright lies that one would expect.

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  2. “Judges should be more skeptical. They should ban junk science from courtrooms.”

    Politicians should be more skeptical. They should ban junk science from policy decisions.

    Begone, AGW!!

  3. Is it deja vu or did I read this article in the last day or two?

    1. Mutual exclusivity premised questions are junk science.

    2. Not an article, but there was a John Stossel video on this topic posted in the last couple of days.

  4. Karazulas sounded impartial and objective. “A forensic scientist is not on the side of the prosecutor or defense,” he said on Cold Case Files. “We look at the evidence.”

    Haaaaaaaaaaaaa ha ha ha ha haaa! Whew! That was a good one!

    1. OT: The other day you misconstrued my point about governance.

      I said that not all governance is socialistic – and then you accused me of contradicting myself. Governance is not limited to the monopoly public sector variety. Private, consensual governance has existed for centuries and whenever a private corporation, limited liability company or other entity establishes their by-laws, stock purchase and restriction on alienation agreements, and rules for conducting meetings, etc., you have private governance.

  5. Add in field tests and dogs for drugs and magic box’s for dui and you have cash cows for government agents. By

    1. If found guilty of DUI, a person will be put into the magic box. Only the box knows what the punishment will be.

      1. they only put your hand in the magic box and what’s in the box is pain.

  6. “We all went to law school because we don’t know science, we don’t know math,” he replied.

    “We don’t know logic, we don’t know nothin’.”

  7. You can’t use DNA evidence anymore, either. It consistently identifies people as male who are, at least this week, female, and vice versa. If DNA can no longer get that part right,m why accept any DNA result?

    1. So you’re saying DNA is bigoted against transgenders?

      1. “Do Not Assess”

  8. We all know from a very popular movie that a “Hewlett-Packard 5710A dual column gas chromatograph with flame analyzation detector.” is very persuasive in a jury trial. We also should know that in a civil or criminal trial the expert witnesses are hired guns.

    A trial lawyer I know explained to me that expert witnesses tend to cancel each other out.

    What is left after all that is not science nor reason. It is all drama and persuasive tactics.

    The reason I am against the death penalty in practice has nothing to do with some sort of eternal justice. It is because I do not trust the courts to deliver it.

    In the first century a historical text said it this way.

    “The Sanhedrin (court) that executes one person in seven years is called “murderous.” Rabbi Elazar ben Azariah says that this extends to one execution in seventy years. Rabbi Tarfon and Rabbi Akiva say, “If we had been among the Sanhedrin, no one would ever have been executed.” Rabbi Simon ben Gamliel responds, “Such an attitude would increase bloodshed in Israel.” Makkoth (7a)

    Differences in legal opinion in matters of life and death are nothing new.

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  10. Greats points raised concerning forensics not being infallible. Keep in mind often times a defendant is appointed an attorney. That attorney is under funded, carries a case load of 40-60 cases, and appears in front of the same judge on a repeated basis – hence dragging out litigation in one case may not be in his/her client’s best interest in another case. In essence, with over 350 people having been released from death row or life imprisonment, it is indeed true that sometimes it is the prosecutor and police who will withhold, plant, and falsify reports to gain a conviction. Looking at the innocence projects website, this has occurred hundreds of times. Hence, not only may forensics be infallible, but so to the people who use it to put people in prison. Best to all, Darren Chaker

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