Last week the Supreme Court heard argument in a case that seeks to establish a rule of accountability for prosecutors who run amok. It arises from a gross injustice. In 1977, Terry Harrington and Curtis McGhee were arrested for the murder of John Schweer, a retired police officer in Council Bluffs, Iowa. They were convicted and spent 25 years in prison. Then it came out that they were innocent of the crime, and that the prosecutors had withheld exculpatory evidence and cajoled and possibly offered money to a witness to give bogus testimony. Harrington and McGhee are now seeking compensation from the prosecutors under a federal statute, 42 U.S.C. § 1983, but they’re running smack into the doctrine of prosecutorial immunity.

No organization has more at stake in this fight than the Department of Justice, and Deputy Solicitor General Neal Katyal was there in court to make their case. There is no “free-standing due process right not to be framed,” he insisted. Judge Stephen Breyer cut him off with obvious dismay. “There is no free-standing right? There is just a right not to convict a person with made-up evidence.” This framing of the issue of framing puts the emphasis where it belongs. The case will turn less on the rights of the two men who spent most of their lives in prison than on the rights of their prosecutors. The law as Katyal spins it gives prosecutors a right to game the legal system and commit crimes in the process without accountability to their victims. Can that possibly be the law? Dahlia Lithwick gives us an excellent summation of the oral argument in “The Framers on the Framers.”

Promoters of prosecutorial immunity offer predictable arguments that devalue justice. In their world, the Court needs to focus on the “realities” of an overworked criminal justice system, whose success is measured by the number of convictions it cranks out. In 2006, Katyal notes, there were 14.4 million arrests and 1.1 million felony convictions. If the courts have to entertain a suit every time prosecutors fabricate some evidence, how will we cope? Moreover, Katyal argues, “if prosecutors have to worry at trial that every act they undertake will somehow open up the door to liability, then they will flinch in the performance of their duties and not introduce that evidence.” But Katyal forgets the flip side. If prosecutors have absolute immunity, what will stop them from using evidence that they may have fabricated or created through undue influence? Shouldn’t prosecutors hesitate before committing wrongful, possibly criminal acts?

Still, the Justice Department is on a roll. Over the last decade it has successfully advanced doctrines of official unaccountability across the board. The Second Circuit’s decision in the Arar case will stand as a monument to these efforts. Roberts, Alito, Scalia and Thomas have a great appetite for immunity for government actors. They remind us periodically that the Constitution makes no absolute guarantees of justice–unless, of course, we’re talking about corporations, in which case the Constitutional guarantees suddenly become extravagant. Sotomayor, Breyer, and Ginsburg all engaged in questioning suggesting they were taking quite a different approach. As usual, the question is likely to come down to Kennedy, a conservative Californian at the court’s center-right middle ground.

The argument for prosecutorial immunity also rests heavily on the ability of professional organs to regulate themselves. This means the Department of Justice above all others. But the last decade has seen an explosion of prosecutorial misconduct in cases around the country. Some arise from a prosecutor’s natural longing to secure a conviction and close a case, but the U.S. attorneys scandal also ripped the cover off a widespread practice over the last eight years of bringing and squelching prosecutions for purely partisan political purposes. Indeed, in what is now the single most prominent case, involving former Alabama Governor Don Siegelman, credible allegations from within the prosecution team itself establish that the same abuses occurred as in the case now before the Supreme Court: bogus evidence was used, and a witness was improperly cajoled to give bad testimony. Yet when this evidence came out, the Justice Department launched a shocking vendetta against the internal whistleblower and quickly swept the matter under the carpet.

The doctrine of prosecutorial immunity may be about to take a hard fall. That would be a curious development in one of the most conservative Supreme Courts of the last century. If so, it will reflect not only concern about the accountability of prosecutors, but also a growing sense that the Justice Department is not doing its job in reining in those who misbehave.