Can anyone please explain to me why a district attorney wouldn t want to bring up DNA?
Can anyone please explain to me why a district attorney wouldn t want to bring up DNA results in a case and your Attorney didn t make a big deal over it either,
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answers:
Smeghead say: Perhaps the case was a minor speeding fine. For instance.

Context is rather important, which you don't seem to have bothered to understand.
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Bela say: Maybe they were non-existent or inconclusive.

Say the blood sample was degraded and the DNA analysis didn't eliminate you as a suspect but also couldn't conclusively prove it was you, and say that the only thing that could be determined from the blood evidence was that its type is O negative, and say that your type is O-negative.

In the example situation above, the prosecution wouldn't bring that evidence up because 7% of people have type O-negative blood. If the prosecution already has a strong enough case, trying to use such flimsy evidence as proof could make their case look weak and stands to open the door to the defense flipping it around and on them and using it to create reasonable doubt, because 7% of the US population creates 14.2 million suspects nationwide other than you, the defendant.

On the other hand, your defense attorney wouldn't bring it up either, not unless the prosecutor tried to use it against you. That's because it doesn't exculpate you, making it completely irrelevant to any defense. Since it instead is evidence that you could've done it, the defense introducing it could even be grounds for a legal malpractice suit by you against the defense attorney because the defense introducing it cannot help your case but can prejudice the jury against you as some jurors might think that 7% is pretty rare and it'd be a pretty odd coincidence for whoever did it and you to happen to have that same, relatively rare blood type.

So, what you've got is evidence that you could've done it but also evidence that 14.1 million other people in the US could've done it, too. As such, the prosecution won't use it because it doesn't prove you did it and because using it could easily backfire on the prosecution, and the defense won't use it because it doesn't prove you didn't do and using it could backfire on the defense.

Essentially, that evidence is radioactive, kryptonite to whoever introduces it. Both sides are actually hoping the other side introduces it, because both sides have a sure-fire way to make the other side look bad and weak for introducing it. But if the attorneys for each side are smart, neither side will take the bait and it won't get introduced.
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history say: No one was ponying up to pay for DNA collections and testing? Real life is not CSI.
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Simpson G. say: Uh, because it’s not relevant?

You didn’t exactly give us any details and DNA doesn’t apply to most criminal cases. I got a speeding ticket - why would I bring up DNA??

My friend got arrested for drunk and disorderly. DNA had nothing to do with him getting drunk and walking down the middle of the street.
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