In television's long-running "Law and Order" series, the prosecutors are portrayed as dedicated searchers for truth who seldom, if ever, fail to find it, and the defense attorneys are depicted as a necessary evil, capable of devious action to free their clients, who everyone knows are guilty. Other entries in the legal free-for-alls that have been a TV staple have taken just the opposite tack, giving the edge to those representing the downtrodden accused. Reality, of course, lies somewhere between, with the justice scales tipping one way or another on an individual basis. But it is safe to say that the modern prosecutor now bears a share of the blame in a series of dramatic instances that make it clear that ambition at the expense of truth is often a motivating factor.

The blizzard of revealed cases of unjust jailing for everything from murder to rape is breathtaking. More than 100 of those sentenced to death or life in prison have been freed by scientific evidence and prosecutorial misconduct, and efforts are underway to make DNA testing mandatory where possible, especially in capital cases.

But few cases of ethical laxity reach the magnitude found in the conviction of Ted Stevens, who until his defeat in the last election was the longest-serving member of his party in the U.S. Senate. At the recommendation of U.S. Attorney General Eric Holder, Stevens' conviction was overturned and six members of the Justice Department team involved in his case face investigation and possible indictment. So furious was the presiding federal judge, Emmet Sullivan, that he ordered a special inquiry into the action of the government's lawyers.

Stevens lost his bid for reelection narrowly after his indictment, and there seems little doubt that he would have been sent back to Congress otherwise. Sadly, it appears there was plenty of suppressed evidence that might have exonerated him or even convinced a more prudent prosecutor not to indict in the first place. There have been calls for a new election, but that seems doubtful.

After the conviction, an FBI agent came forth to blow a whistle, and Holder conducted his own investigation. He was appalled, concluding quickly that there were major ethical and possible legal breaches within the department, including the devastating withholding of notes that would have suborned the testimony of the key witness.

If there is a glimmer of hope for the system, it is in the new attorney general's quick recognition of impropriety. Holder also moved rapidly to overhaul the department's Office of Professional Responsibility. So often prosecutors refuse to concede flaws in their actions. Their standard response is that the jury has spoken, even when the most legally untutored of us understands that most panels ignore the reasonable doubt mandate, shifting the burden of proof to the defendant.

Henry Peterson, who was the career head of the Justice Department's criminal division and a key figure in the investigation and prosecution of Watergate, demanded of his lawyers that any case brought against a public figure be 99.9 percent provable. The potential damage otherwise, he said, could be devastating.

Stevens, at 85 and still vital and irascible, is clearly a case in point. Both the system and the man are victims.