Search for an Assailant

PAUL MCLAUGHLIN, an assistant attorney general in Massachusetts, was gunned down earlier this week at a train station in West Roxbury, a white, middle-class section of Boston. That much police know. What they still don't know is whether Mr. McLaughlin was targeted by the gang members and drug dealers he prosecuted.

Because of the nature of the crime and the concern that it might have been an attack on the criminal justice system itself, McLaughlin's killing has set off an intensive investigation. A small army of law-enforcement officers has been put on the case, and police are offering a reward for information leading to an arrest.

The response is warranted. The victim's father spoke for many when he said, ''If they don't stop this, there's no telling where we're going as a society.''

Prosecutors who worked with McLaughlin insist they won't be cowed by the killing, saying McLaughlin's death has only strengthened their resolve. Their message is important for everyone: We mustn't be held hostage by perpetrators of violence or by those who would exploit the fear of violence, as one local pastor said.

But neither should we jump to conclusions before the facts of this case, or any case, are known. Boston's African-American community is - justifiably - concerned that the search for an assailant could escalate into a racial witch hunt. They remember what happened in 1989, when police indiscriminately rounded up black men in Boston's inner city after the slaying of a white woman, Carol Stuart. Soon after, her husband, Charles, killed himself when his claims of a black assailant began to crumble and he wa s implicated in her death.

This time, police have appealed for help in the inner city. They realize their description of the suspect - a black male wearing a hooded sweatshirt and baggy jeans - is vague and that action based on it could be divisive. They have promised that their investigation will be broad and methodical, the kind McLaughlin conducted.

The victim left another important legacy: He was known as a prosecutor with common sense, one who wasn't out to convict at all costs.