There were two perfectly predictable schools of thought being expressed after the conviction of Jose Padilla on Thursday on terrorism-related charges. Supporters of the Bush administration said the conviction justified the more than three years Mr. Padilla spent in military detention before his criminal prosecution, while the administration's opponents said the verdict proved that the criminal justice system should have handled the case in the first place.
But the real innovation in Mr. Padilla's case, some legal experts said yesterday, was more subtle than those dueling talking points suggested. The Justice Department's strategy in the trial itself, using a seldom-tested conspiracy law and relatively thin evidence, cemented a new prosecutorial model in terrorism cases.
The central charge against Mr. Padilla was that he conspired to murder, maim and kidnap people in a foreign country. The charge is a serious one, and it can carry a life sentence. But prosecutors needed to prove very little by way of concrete conduct to obtain a conviction under the law.
"There is no need to show any particular violent crime," said Robert M. Chesney, a law professor at Wake Forest University and the author of a recent law review article on conspiracy charges in terrorism prosecutions. "You don't have to specify the particular means used to carry out the crime."
Indeed, the strongest piece of evidence in Mr. Padilla's case was what prosecutors said was an application form Mr. Padilla filled out to attend a training camp run by Al Qaeda in Afghanistan in 2000.
"It is a pretty big leap between a mere indication of desire to attend a camp and a crystallized desire to kill, maim and kidnap," said Peter S. Margulies, a law professor at Roger Williams University who has also written on conspiracy charges in terrorism prosecutions.
The conspiracy charge against Mr. Padilla, Professor Margulies continued, "is highly amorphous, and it basically allows someone to be found guilty for something that is one step away from a thought crime."
Prosecutors have long loved conspiracy charges in all kinds of cases. Judge Learned Hand, widely thought to be the greatest American judge never to sit on the Supreme Court, called conspiracy "that darling of the modern prosecutor's nursery" in a classic 1925 decision. More recently, Judge Frank H. Easterbrook, now the chief judge of the federal appeals court in Chicago, lamented that "prosecutors seem to have conspiracy on their word processors as Count I."
But recent terrorism prosecutions are doing more than using an old tool with new aggressiveness, legal experts said. They are also using it for a new purpose: preventive detention.
Before allowing Mr. Padilla to be tried in the federal courts, the administration justified holding him as an enemy combatant in part by saying he would be dangerous if let go. Criminal prosecutions, by contrast, are almost always focused on conduct already committed.
But the sharp split between military detention and criminal prosecution starts to blur as conspiracy charges are added to the mix.
That is because conspiracies aim at the future. A successful conspiracy prosecution looks both backward, to punish the crime of conspiring, and forward, to stop dangerous people from completing their plans. The weaker the evidence of conspiracy is, the more such a prosecution can look like a request for judicially sanctioned preventive detentions.
In opinion articles and academic commentary, lawyers and law professors across the political spectrum have been arguing in recent months about whether the criminal law should be supplemented by legislation authorizing preventive detention. The Padilla verdict suggests that something similar may have already been achieved in the courts.
There was a second justification for Mr. Padilla's prolonged military detention. In a sworn statement in 2003, Vice Adm. Lowell E. Jacoby, then the director of the Defense Intelligence Agency, told a federal judge in New York that Mr. Padilla should be interrogated without access to a lawyer.
"It is critical to minimize external influences on the interrogation process," Admiral Jacoby wrote. "Anything that threatens the perceived dependency and trust between the subject and interrogator directly threatens the value of interrogation as an intelligence-gathering tool."
That sort of intensive and isolated interrogation, which Mr. Padilla lawyers have said caused him lasting psychiatric problems, could not have been accomplished in the criminal justice system, where the Constitution guarantees legal representation and other due process protections.
But Justice Sandra Day O'Connor, in her controlling opinion in Hamdi v. Rumsfeld, the 2004 Supreme Court decision that endorsed the detention of at least some enemy combatants to prevent their return to the battlefield, rejected interrogation as a rationale for detention.
That same year, the Supreme Court ruled on a procedural question in the Padilla case but did not discuss whether his detention was proper. Just before the Supreme Court was to decide whether to hear his case again, the administration moved him to the criminal justice system.
If Thursday's verdict is upheld, the administration may thus have achieved the last in a series of practical victories. It held and interrogated Mr. Padilla without interference from the courts, and now it has convicted him of a crime that could put him away for life.
Copyright 2007 The New York Times Company