It was an ordinary Wednesday afternoon at Springfield Mall in suburban Philadelphia when a young woman dressed in army fatigues and carrying a .22 semi-automatic rifle stepped out of a car and began firing in the parking lot. As she moved toward the building she shot at two children, killing a 2-year- old boy. Inside, she fired at random, killing a 64-year- old man and wounding eight others. The woman charged in this horrible assault is Sylvia Seegrist who, in the past 10 years, has been in and out of 12 mental hospitals and is alleged to have been involved in two earlier violent attacks.

It has become almost a clich,e that when some terrible crime has been committed friends and neighbors of the accused show surprise: "Not Elbert! He was such a sweet, quiet boy." That was not the case with Miss Seegrist. Her own mother, whom she once tried to strangle, described her as "terribly psychotic." Former roommates said they were afraid of her. Her pastor told the press, "Sooner or later we knew she would explode." One neighbor characterized her as a child hater and "the most aggressive, violent person" he had ever known. Another said that when he heard radio reports of the shooting he knew exactly who must have done it.

What was an extremely dangerous mentally ill person doing walking around the streets? Why were courts unwilling to listen to the pleas of her parents and doctors for involuntary commitment when there was a history of violence and good reason to believe it would recur? In New York last week, another young woman who had been released from a mental hospital over the objections of psychiatrists was charged with pushing a stranger in front of a subway train. Judges, like all of us, make mistakes, and it is easy to assign blame in hindsight. And, of course, any deprivation of liberty must occur only after careful and fair proceedings on the issue of the danger. But the problem goes beyond a couple of cases to a general attitude that involuntary commitment is to be avoided at almost any cost. Surely this policy, as applied to violent people, must be reevaluated.

And does it make any sense at all that a woman with Miss Seegrist's record can easily purchase a semi-automatic weapon over the counter? These rifles are for sale, and anyone can walk off the street, sign a statement that he is not a felon or a former mental patient, and buy one. No one need check the accuracy of that disclosure. The gun lobby continues to oppose even the most modest restrictions on the most deadly weapons. Tragedies such as this one should lead lawmakers to seek sensible controls.