Bill Cosby's lawyers have filed a motion to dismiss his criminal case based on an alleged agreement made with the prosecutor's office back in 2005. He's actually got a shot at getting the case dismissed, or at least excluding some of the evidence the prosecutors want to use. But like many issues in this case, it's complicated.
Back in 2005, Cosby was in a "parallel proceedings" situation, facing the possibility of both criminal and civil exposure. Like all defendants in such situations, he had a difficult choice to make. A defendant in a criminal case has an absolute right not to make any statement that could incriminate him, and most defense attorneys will advise their clients to say nothing at all, at least until trial. On the other hand, a defendant in a civil case is typically expected to submit to a deposition in which the plaintiff's attorney can ask probing, wide-ranging questions.
As I've discussed in more detail here, a defendant facing possible criminal exposure has a right to remain silent even in a civil case (because statements made in a civil case could be used in a criminal case), but there's a cost to doing so. Keeping silent hinders the defendant's ability to defend himself in the civil case, and under certain circumstances his silence can be used to support an inference of liability (an inference that's impermissible in a criminal case).
Normally, someone in the situation Cosby was in back in 2005 would be advised not to answer deposition questions, because the risks on the criminal side typically outweigh any benefit from giving deposition testimony in the civil case. Cosby did answer those questions, though, and we may now know why. According to Cosby's lawyers, the prosecutor overseeing the criminal case agreed that if Cosby answered deposition questions in the civil case instead of invoking his Fifth Amendment privilege, he wouldn't be criminally charged for the conduct at issue. That prosecutor has apparently acknowledged the existence of an agreement, albeit perhaps with different terms. According to a recently disclosed email, the prosecutor claims to have agreed that if Cosby testified in the deposition that testimony wouldn't be used against him in any criminal case.
Assuming some version of that agreement was made, is it enforceable, and can it help Cosby now? Quite possibly, yes--although the rules aren't quite the same as those applicable to "ordinary" agreements.
One difference is the point at which an agreement becomes legally enforceable. In many settings, an agreement becomes binding the moment it's reached--that is, as soon as there's a "meeting of the minds." So if you offer to buy my watch for $10, and I agree, at that moment we have an enforceable agreement. If you change your mind a few seconds later, I can still enforce the agreement, either by requiring you to pay me the agreed-upon price for the watch or by compelling you to make up the difference if I sell it to someone else for less.
In criminal law, an agreement typically only becomes enforceable after the defendant "detrimentally relies" on the promise made by the prosecutor--that is, if the defendant does something in reliance on the promise that he wouldn't ordinarily have done, and that could harm him if the promise isn't fulfilled.
Here, assuming there was in fact some type of agreement, proving detrimental reliance shouldn't be difficult. Testifying in the civil deposition was something Cosby had a right not to do. If he did testify in reliance on the prosecutor's promise, that gave the prosecution evidence it could use against him if charges were ever filed--indeed, the current prosecutors have cited that deposition testimony as a significant reason for reversing the original nonprosecution decision. Accordingly, based on that reliance the court may well enforce the agreement and prevent the prosecution from going forward.
Alternatively, the court may issue an intermediate remedy and allow the case to proceed, but without the use of the deposition testimony. This could happen if the court decides that the actual agreement was only to refrain from using the testimony, but even if the court accepts Cosby's characterization of the agreement it could still issue that intermediate remedy. In reliance situations, courts occasionally enforce an agreement only to the extent necessary to remove the harm from the detrimental reliance. Here, that could mean trying to put the parties back in the position they were in before the promise and Cosby's reliance, which could mean forbidding use of the testimony.
Cosby's lawyers will argue that that's not enough--that even if the State can't use the testimony itself, it would still have the benefit of any investigative leads or other "derivative" evidence it wouldn't have had if Cosby had invoked his privilege. Accordingly, they'll say, the only sufficient remedy is dismissal.
In case that's not complicated enough, there's another wrinkle. Occasionally courts will decline to enforce contracts that are "against public policy"--that is, if recognition and enforcement of the type of contract at issue would generally be bad for the community.
This can come up with contracts relating to criminal cases, particularly when money or other compensation is involved. There's a general discomfort with the idea of defendants "buying their way" out of criminal charges; this is sometimes made expressly illegal by statute, and even when it's not courts may be reluctant to enforce any associated agreement. (Of course, in many cases wealthy defendants are in fact able to avoid criminal liability through some form of monetary compensation. When this happens it's often done subtly and delicately, and not in reliance on express agreements; one result is that if someone has second thoughts the "agreement" may be difficult to enforce.) This issue may affect the overall analysis of whatever deal Cosby's lawyers and the prosecutor reached back in 2005.
Cosby may well get at least a partial win here, with the court limiting or prohibiting the use of the deposition testimony even if it doesn't dismiss the case. But as with everything else in this case, we'll have to wait and see.