We all know justice is supposed to be blind, so that she won't be swayed by superficial details. She's above all that, weighing the charges against the evidence and coming out with only the truth. Well, that's how it's ideally supposed to work. But the problem with the machinery of justice is that it gets all gummed up by us humans. Even the most seemingly rock-solid legal evidence can wind up more full of shenanigans than an Irish frat house. For example ...

5 Fingerprints Are Scientifically Unreliable

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Come on. Fingerprints are solid evidence. They have to be. They're fingerprints. Surely every single TV show in history didn't lie to us. Every single person's fingerprints are different, so they're a foolproof way to identify who's touched something. We've been using them in criminal cases since the 19th century, for Pete's sake!

How It Can Go Horribly Wrong:

Your fingerprints might not be all that unique -- and even if they were, there are a large number of variables that can make technically different prints seem very similar. See, getting the perfect fingerprint from a crime scene is something of a white whale. As often as not, investigators are lifting partial prints, which is how things can go haywire. Maybe fingerprints of you and Strong Dong Johnson, the Philadelphia Penis Strangler, share a bit of a coincidental similarity. A spot of bad luck later, and you're on trial for crimes of the dick. Or what if your family member commits a crime? Yes, families share certain elements of their fingerprint patterns. Your brother's the peeping tom, but you're the one getting hurled in the back of a police cruiser.

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"This is bullshit! I only creep on Instagram. He's the analog one."

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Although there are standards for determining fingerprint patterns, the actual matching of them is entirely on the shoulders of the expert handling the case. As such, fingerprint identification is an extremely delicate art. And by "delicate," we mean "wildly subjective." Experiments have found that even highly respected experts can be biased, to the point where they can change their minds about the same exact set of fingerprints based on what they know about a case.

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"He lost both hands while saving blind puppies from terrorists in Iraq."

"That's what they all say."

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Still, old habits die hard. We've always been told that fingerprints are indisputable, and so that's what we believe. At least, right up until your brand-new fingerprint-scanning door slides open in the middle of the night and you find out that Strong Dong Johnson doesn't appreciate you taking credit for his work.