Anyone want to bet me that these two former federal prosecutors that The Hill just happens to have on speed-dial are now themselves defense lawyers and active Democrats? In any event, the claim that the GOP investigation of Fast and Furious is now raising the specter of violent criminals getting their convictions reversed is about as frivolous as it gets.
Let’s begin at a very high level of generality. Defense lawyers will use anything as a pretext (or what the Hill portrays as a justification) for seeking a mistrial. Once your client has been convicted, what have you got to lose? The mistrial motion does not need to have any real merit to it in order for it to be filed. It is cost-free — except what you may have to pay a defense lawyer to prepare it (and most such “habeas corpus” motions are filed by defendants without the assistance of counsel — i.e., “acting pro se,” as we say in the biz). From the defendant’s perspective, the worst thing that happens (and it always happens) is the judge denies the motion. Nothing changes.
But now, let’s get to a more specific analysis. There is a mistrial motion available in the law — one the Supreme Court made up out of whole cloth — for what is known as “outrageous government misconduct.” But it is limited to outrageous conduct in the evidence-gathering process by the investigative/prosecutorial authorities. Best example is probably the case that started it all: Rochin v. California. Los Angeles deputy sheriffs, who did not have a warrant, broke into the defendant’s home and saw him grab and swallow the illegal narcotics they suspected he had. They proceeded to drag him down to the hospital and have his stomach pumped so they could recover the drugs — again, without a warrant.
Nowadays, the case would just be decided on the exclusionary rule: the warrantless arrest and search would be deemed illegal, and the drugs suppressed as “fruit of the poisonous tree” — a sort of due process gloss the courts added to the Fourth Amendment guarantee against unreasonable searches. But back when Rochin was decided in 1952, the Supreme Court had not yet applied the exclusionary rule against the states. (That happened in the 1961 Mapp v. Ohio case.) So if Felix Frankfurter and his fellow justices wanted to invalidate the very unattractive Rochin case, they had to come up with some other reason. So, as often happens, they manufactured one: a vague new due process right to seek to have an indictment dismissed if the government conduct is so outrageous as to “shock the conscience” of the court.