Washington — Ruling that John W. Hinckley Jr. is still ''dangerous to himself and others, '' a federal judge committed the young presidential assailant Monday to an indefinite term in a mental hospital.
Hinckley, who successfully pleaded not guilty by reason of insanity and claimed he shot President Reagan and three others because of his love for actress Jodie Foster, did not contest government prosecutors' claims that he requires treatment.
But prosecutors, who spent several weeks at trial arguing that the defendant was sane, sought Monday's hearing before US District Judge Barrington Parker as a formality, to ensure that Hinckley's indefinite commitment is not shortened by any future claim that he was denied his right to a commitment hearing. It is the ''indefinite'' element of the commitment ruling that promises to keep the insanity defense a burning issue. Unsettled by the fact that Hinckley could admit to the shooting, yet come away with the rights of a mental patient rather than the penalties of a convicted criminal, Americans probably will see the issue surface regularly with the biannual review of Hinckley's sanity.
Initial public reaction to the Hinckley acquittal was a direct assault on the insanity defense - attempts to ban it altogether, provide for a ''guilty but insane'' verdict, or simply require more accountability from those acquitted on grounds of insanity.
US Attorney General William French Smith, who reportedly rejected a Hinckley plea bargain that would have guaranteed the young man a federal prison sentence, last month offered support for a Senate bill that would essentially bar the insanity defense in federal criminal trials.
In support of the proposed law at a Senate subcommittee hearing, he described its intent this way: ''S2572 would effectively eliminate the insanity defense except in those rare cases in which the defendant lacked the state of mind required as an element of the offense. . . . A mental disease or defect would be no defense if a defendant knew he was shooting at a human being to kill him - even if the defendant acted out of an irrational or insane belief. Mental disease or defect would constitute a defense only if the defendant did not even know he had a gun in his hand - or thought, for example, that he was shooting at a tree.''
Mr. Smith also said the bill would eliminate the question of whether a defendant knew his actions were morally wrong and whether he could control his behavior. It would also eliminate ''the presentation at trial of confusing psychiatric testimony on the issue,'' while leaving insanity to be considered at the time of sentencing, he said.
Hinckley's attorneys successfully argued, as current law allows, that while the young man may have known he was shooting at people, he did not know it was wrong and was unable to control his actions.
Besides the calls for an outright ban on the insanity defense, the Senate's three days of hearings brought together others who advocate modifying the law, including psychiatrists, attorneys, a federal judge, and five jurors in the Hinckley case.
Testimony focused on concern that while federal law offers insanity as an defense for a crime, it goes no further, leaving judges ''powerless'' to control a person found criminally insane. Except for a District of Columbia law mandating commitment after an insanity verdict, there is no specific federal provision in the 50 states authorizing a judge to keep tabs of a defendant acquitted on grounds of insanity.
Other testimony suggested that no standards for release exist, so judges are often required to use unscientific methods for determining the future danger a defendant poses. Regarding the questionable statistics available to courts on the probability of a defendant committing a subsequent act of violence, one legal scholar told the subcommittee, ''You and I could stand here and flip coins and make as accurate a prediction as a clinician.''