Will John W. Hinckley Jr.'s prison term--if any--begin before Ronald Reagan's presidential term ends?

Five assassins were sentenced five months after Egypt's Anwar Sadat died. Less than two months passed between the arrest and conviction of Gen. Dozier's Italian kidnappers. Less than 10 weeks passed between the shooting of the pope and the conviction of his assailant. The man who in 1933 tried to shoot FDR but shot Chicago's Mayor Anton Cermak instead was tried, convicted and electrocuted two weeks after Cermak died. But we are now in the second year after Hinckley's attack on the president, and his trial is not even about to begin.

Last Wednesday, the Supreme Court reinstated the murder conviction of Dr. Jeffrey MacDonald, the former Green Beret who was convicted in 1979 of the murder of his wife and children. He claimed that his constitutional right to a "speedy" trial--an undefined term--was violated because civil authorities did not indict him until 1975, four years after the Army dropped charges against him. The murders occurred in 1970. Now he almost certainly will raise other challenges to his conviction.

Hinckley's case may become another conspicuous case that deepens suspicions that there is too much procedural sand in the judicial gears. Those suspicions are not groundless. But Hinckley's case is too peculiar to be illustrative.

When someone shoots a president in broad daylight at close range in front of cameras, he does not have a wide choice of defense arguments. An insanity plea is not surprising; it is barely optional. But such a plea launches scientific, quasi- scientific and pseudo-scientific arguments that are hard to terminate.

Usually the purpose of a criminal trial is to determine whether a particular person committed a particular act. The focus of Hinckley's trial will be the mental state of the person at the time when he is known to have committed the criminal act.

Such a trial is apt to involve, immediately, confinement for observation to determine fitness to stand trial. Then comes retrospective argument about his ability to conform his conduct to the law at the time of the crime.

Hinckley's attorney is attempting to suppress some evidence, including some gathered from him immediately after the shooting, when the FBI was rushing to establish that he was not part of a conspiracy. Because this evidence was gathered before he had legal counsel, the defense wants it excluded, to prevent the prosecution from using it to establish that Hinckley was rational at the time.

Criminal cases often focus on mental states: did the defendant knowingly and intentionally disregard a legal duty? A humane society must provide some place for arguments about a defendant's diminished mental competence and, hence, diminished culpability. Certainly there is a prima facie case for considering anyone "disturbed" who does the sort of thing Hinckley did.

But that settles nothing. In defining the burden of proof regarding an insanity defense, the traditional questions have been: was the defendant capable of appreciating the nature and quality of his act? Was he competent to respond to the commands of the law? The answer to both questions can be "yes" regarding people who are "disturbed." But abstruse medical and other theories of competence are proliferating, as is to be expected in the absence of scientific consensus.

Hinckley is, of course, an uncommon defendant. And an insanity defense is quite unlike the procedural considerations that often are blamed, often unfairly, for protracted criminal proceedings.

Most defendants are guilty, and are in no hurry to come to trial. Courts have elaborated procedural "safeguards"-- principally, "Miranda" (right to counsel) and Fourth Amendment (search-and-seizure) protections--that are not clearly grounded in the Constitution. This is not to say that such safeguards are primarily responsible for protracted, even dilatory, criminal trials. But such trials do take a toll against public safety, the public's esteem for the judicial system, and even the self-esteem of those who operate the system.

A fetish often indicates a deeper disturbance, and the fetish that some judges have made of some procedural safeguards indicates a liberal society's uneasy conscience about punishment generally. A society that does not believe in evil, that defines sin as sickness, that assumes "deviant" behavior derives from correctable flaws in the social environment-- such a society is apt to feel a bit guilty about the very idea of punishment.

In a liberal society, it is thought vaguely "progressive' to consider punishment (as distinct from "correction") as faintly retrograde. In such a society, there is a lot of money to be made selling handguns and deadbolt locks.