[tptacek]

You're getting a lot of huffy responses to this question, but it is an entirely legitimate one. In fact, many (maybe most?) western countries don't have the same exclusionary rules the US has. There are other remedies to police misconduct. If you were starting a nation from first principles, it's not an iron law of justice that your courts have that rule.

The reason we believe the exclusionary rule works so well is that it strikes directly at the incentive structure for the police. We don't have to convince evidence-gathering officers of their liability or assess liability up and down the chain of responsibilities on the prosecution's side; we just have to assess whether evidence was handled properly, and, if it wasn't, the prosecutors lose the evidence. The one simple rule neatly ensures that nobody --- in any role --- on the prosecution's side has any incentive to mishandle evidence (or coerce underlings or partner organizations to mishandle it).

But clearly the rule isn't a requirement. We don't generally believe, for instance, that Canada's criminal justice system is systemically corrupt, and they don't have a hard-and-fast exclusion rule.

[AnthonyMouse]

> The reason we believe the exclusionary rule works so well is that it strikes directly at the incentive structure for the police.

It also strikes directly at the incentive structure for defendants.

If you prove that the government wronged you but even then you still go to jail, you have little incentive to spend your resources proving that. And neither does anybody else, because prosecutors are not very interested in looking for prosecutorial misconduct.

But if proving government misconduct will keep you out of jail then you have every incentive to do it and the government won't be able to get away with it as much.

[waqf]

> incentive structure for the police

That assumes that the police's incentive is simply to convict as many people as possible. Which, if true, raises other concerns.

[setr]

I think it more assumes that the police's incentive is to maximize the ratio of accusation to conviction as much as possible, which is a reasonable goal.

If they were simply trying to maximize the total number of convictions, then this wouldn't necessarily help; the police would just make broaden the kind of cases they'd accuse

And ofc, it's the function of the police to maximize the misdemeanor to conviction ratio; it's the function of the court to judge the quality of misdemeanor.

It is the function of whatever social/moral arm of the government to minimize misdemeanors. A police officer minimizing the number of accusations should only be doing so for practical reasons; In the ideal world he shouldn't be trying to interpret the law itself, and if it should exist (because it should in general be explicit what is and is not legal, and in general, it is not the policeman's job to decide what is moral, it is to enforce the standing morals.)

But its not an ideal world, and nobody wants to spend time/effort/money on a trash case, so the general incentive is to successfully convict; not to simply try.

[foldr]

>I think it more assumes that the police's incentive is to maximize the ratio of [conviction to accusation] as much as possible, which is a reasonable goal.

Strictly speaking it's not a very reasonable goal. The best way to achieve it would be to pick, say, the three easiest to prosecute cases every year and only prosecute those.

[setr]

Well shit

Maximize ratio and minimize unaccounted (unaccused?) crime

[ScottBurson]

> maximize the ratio of accusation to conviction

Um -- I think you meant that the other way around :-)

[setr]

yes

[hawkice]

I mean, illegally obtained evidence is still evidence. I don't think it's absurd to think police want to convict as many guilty criminals as possible, particularly if the crime is heinous enough to justify risking their own jobs by breaking the law to get evidence.

[fl0wenol]

When we no longer have elected police, sherrifs, or district attorneys, then the numbers won't matter as much as the severity or sensationality of the crimes investigated.

But if the numbers = tough on crime, then there is pressure to obtain evidence illegally. If it becomes pervasive, then investigating the misconduct will never be prioritized because it doesn't seem as impressive to the voting public, and furthermore the justice system very rarely goes after their own.

So it's good there's a consequence for not walking a fine line; it's the embarassament of having your work undone.

[mkesper]

This would open the doors for torture, not something a civilized state should risk lightly.

[mirimir]

> The reason we believe the exclusionary rule works so well is that it strikes directly at the incentive structure for the police.

That's debatable. Parallel construction seems pretty common. The NSA shares information with the FBI, DEA etc, and then they exploit that information to collect clean evidence. So there's never any mention of NSA help.

Of course, that arguably involves perjury. But judges seem pretty OK with ignoring that. I do suspect that the Playpen cases involved parallel construction, and that they just screwed up on this one.

[tptacek]

By "pretty common", you mean, "I've heard of it", right?

[mirimir]

Point taken. But I've heard repeatedly about it, involving different sorts of illegal data, over some years. And the discovery rate is arguably low. That suggests to me that it's common.

[hydrogen18]

You're actually missing a huge point in this, it gives the police the ability to selectively block the justice system.

If a police officer sees a defendant that they wish to let off the crime, all they have to do is testify to some trivial mishandling of the evidence.