Preventing overcharging by prosecutors

I think that accuracy is better for a prosecutor to optimize then not overstating the likelihood. 

If I'm charged with a crime and the prosecutor tells me that the real chance of getting put into jail is 60% when it's actually 90% then I'm harmed by having more hopes then reasonable about being able to stay out of jail. 

Besides the main number, all the history should however be available so that a defense lawyer could also calculate whether a prosecutor with a bad Briers score under or overcharges.

In addition to accuracy being useful to optimize for, I expect it to be easier to find a political consensus around "prosecutor should be accurate when making charges" as that's desirable for both the right and left. 

For something that's impossible to implement, this seems like a surprisingly small step 

I don't believe that it's impossible to implement. Good policy making is about adding a lot of small steps together. It's one small step that can be added to a legal reform bill in any state. 

We have a climate where a liberal US state might very well say: "Let's put all reasonable proposal to improve our legal system into a bill and put it up for a vote".

Here it's also worth noting that we are at a time where crypto people are inventing new legal systems. https://kleros.io/ for example is really interesting. 

OR to resolving the broken incentives of prosecutors (convictions, not truth).

This system doesn't completely change the incentives of prosecutors for convictions to truth but it moves them in that direction. 

Consider the case of an illegal search that definitively proves guilt, but cannot be presented at trial.

Disincentivizing gathering information from illegal searches is a feature and not a bug. The fact that the process I propose has side-effects like discouraging illegal activity like that shows it's power.

I don't think the system should be designed to give people who do illegal things more room to maneuver but to reduce that room. 

Also, too, predicting outcomes is a skill separate from ability to generate outcomes.

The present system in the United States doesn't select for the outcome of prosecutors persuing justice but often rewards them for doing unjust things like maximizing the amount of people they put behind bars. 

I do think that prosecutors who's mental focus when charging a person isn't "how do I maximize the chances of getting this person behind bars" but who are also taking the outside view and think clearly through the likelihood of the person being convicted being are more likely to persue justice. 

Also, also, too almost no prosecutors are directly elected, judging people by any raw metric is wierd and not done 

The point is not to say that this should be the only metric that's used to judge prosecutor performance alone but to design the system so that it's one of the metrics that's visible when decisions about prosecutor performance get made. 

As far as judging people by performance metrics being weird, we do have a problem that many people prefer to judge expertise by college degrees then by actual performance metrics. 

It seems to me like your proposed system is more gameable by influencing the people who do the review and who select which case to randomly review then the system I proposed. 

Furthermore, it does have no direct impact on the decision making process of the prosecutor when pressing charges. 

You only score the predictions that actually have the court decide the outcome or that have the prosecutor drop the charges without a deal and not those that get decided by plea deals. 

I do think that the legal standard of reasonable doubt means not assigning low likelihood charges. That's how I understand the principle of "reasonable doubt". The feature of this system it that it lets the jurors decide what they think reasonable doubt means and the system doesn't set the meaning for it. 

It would be a legal obligation for a prosecutor when making a charge to publically enter the charge along with the likelihood into a database. Making errors with filing charges will be problematic for the prosecutor the same way it's problematic now, it can make a court throw out the charges on procedural grounds. 

Then when an election comes around the election commission has the job to calculate the Briers score to put it on the ballot.

The job of administrating the database could be done be done by the court where the charges get filled, so that it's outside of the realm that the prosecutor can influence.

If upfront assessments are provided, I expect the defense bar would gleefully keep track of such things.

They already informally track the behavior of the DA's offices they deal with. They're extremely organized in some areas and in near-constant communication with one another.

How would prosecutors be trained and incentivized to make and report accurate predictions? Who would be funding the defense attorneys, especially overworked public defenders, to learn to properly evaluate prosecutor's claims? 

The main thing a prosecutor cares about is getting reelect as a prosecutor. Writing the metric that measures whether they are good at reporting accurate predictions and writing it on the ballot is one of the strongest ways to incentives prosecutor.

Even if the prosecutor wants to go to another office after being a prosecutor, doing badly at the metric for prosecutors that gets written on their ballot, will be hold against the prosecutor. 

Shifting the incentives on which prosecutors get evaluated is part of what this proposal is about.

Also, I understand that one of the big issues with plea deals is that it is often in a defendent's individual interest to plead guilty to a lesser charge they're innocent of, even if they're pretty sure they wouldn't be found guilty at trial, either because they're risk averse (not necessarily unreasonable when years of your life are on the line), or because the agreed-on punishment will be less than the time in jail, and cost in fees, they'd incur just by going to trial even if exonerated. Data on likelihood of conviction wouldn't help with that.

Let's say a defendent Joe correctly believes that his chance of being found guilty at trial is 10%. This means that a prosecutor that's well calibrated because that's in his interest for getting reelected would also tell him that his chance of being found guilty is 10%. 

If I'm a risk adverse person then knowing that not only I believe that my chances of being found guilty is 10% but that the prosecutor whose has access to evidence that I don't see also believes the chance is 10% is very helpful. 

Then when I'm in the court room my lawyer can ask the prosecutor "Why did you bring that case when you only think that there's a 10% chance that my client will be found guilty?". Journalists could write story "Prosecutor Smith brings a case against Joe to trial even so he only believes that there's a 10% chance that Joe would be convicted". 

That's not good for the public reputation of prosecutor Smith and thus won't charge Joe in the first place and has no leverage to get Joe to accept the plea deal. 

Who would be funding the defense attorneys, especially overworked public defenders, to learn to properly evaluate prosecutor's claims? 

The same way they are currently learning to evaluate the charges that the prosecutor makes. If the defense completley ignores the numbers nothing is lost over the status quo.

At a more basic level, I think this solves the wrong problem.

Rejecting a proposal because it doesn't solve the problem you most care about it is bad. I agree that it would be good if the penal code would be changed and sentencing guidelines be reduced but that's not the issue my post is addressing. 

In Germany where I live a prosecutor has a legal obligation for prosecuting cases of crimes if he believes the defendent is guilty. A prosecutor is not allowed to say "Well this law is stupid so I won't prosecute people for breaking it" while in the US that's within the rights of a prosecutor. This right allows for plea deals to happen in the US.

If you change this basic part about what the mandate of the prosecutor happens to be, you will suddenly get a lot of very bad laws enforced that currently aren't enforced. If laws against oral sex in some states suddenly get enforced that will create pressure to get rid of those laws but it's won't be pretty. 

But even if the US would get rid of their current legal system and switch to the German one (which is obviously much better thought out and superior ;) ) and have a culture change to make American bureacrats as law abiding as German one's there's still a process whereby plea bargining could cut down on legal costs and time of the trial. There's a benefit in getting a verdict in a few days instead of years through plea bargaining. 

In many situation a plea deal is about more then just getting the person to admit that they are guilty but also to reveal certain other information that's of interest to the prosecutor. Being able to make a deal to get the information can be useful for the government.

As I wrote, I don't think such a number should be set directly by law. 

A judge can however take the number into account when deciding whether there's "probable cause". Individual jurors might also decide to categorically treat charges with are under some number as baseless charges.

A voter might decide that he doesn't want to reelect prosecutors that fill charges with <50% or <75% certainty. Prosecutors who fill charges that they believe to be low probability can be judged for that behavior democratically and different voters can disagree with each other what standards they have for prosecutors. 

Having new dimensions based on which voters can evaluate prosecutors and thus incentvise different behavior for prosecutors then just a maximum of convictions is part of the point. 

The defense attorney doesn't have access to all the evidence that the prosecutor has. This proposal essentially forces the prosecutor to state at the beginning how strong his evidence is.

Having common knowledge about what the prosecutor believes about the likelihood that his charges stick is very useful for the defense attorney when it comes to negotiating a plea deal. 

Being able to argue in court "Even the prosecutor only believes that there's a 10% chance that this charge sticks" is a valuable move even if the defense attorney knows that there's a 10% chance.