A GROUP OF CONSTRUCTION WORKERS Monday provoked a violent confrontation with demonstrators picketing against draft registration in downtown Boston. "We don't want to hear what they have to say," one hard hat said after police had broken up the scuffle.

Across the street, inside the main branch of the Boston post office, federal officers were arresting 22 people for sitting on the floor in an otherwise empty registration room. But the feds, joined by unidentified postal employees, were also breaking cameras, throwing people against walls, and dragging them down stairs. One woman was escorted from the building so enthusiastically that a heavy glass door was shattered in the process, and a youth was clubbed several times on the head after he was arrested.

Nobody was seriously hurt as a result of Monday's violence, but the behavior of the federal guards--clearly not skilled in crowd control--should serve as a warning to police in Boston and Cambridge. Protesters have planned non-violent anti-registration demonstrations for the rest of the week; there is no reason why any of these rallies or sit-ins should turn into dangerous free-for-alls through police violence. Yesterday's picketing in Central Square, for example, produced only verbal confrontations between federal officers and protesters.

If the police feel personal animosity toward demonstrators, as was clearly the case Monday, they must still carry out their responsibilities with restraint. Protesters often announce their willingness to be arrested for conducting civil disobedience. Why then twist arms, knock heads, or break glass doors with bodies?