Indignant denial that Boston is corrupt is nearly as old as Boston's corruption itself. This week Cardinal Cushing added himself to the city's defenders: he insisted that the implications of a nationally televised film showing police visiting a bookie joint on Massachusetts Avenue were false, meaningless, and irresponsible.

Now the Cardinal had never seen the film, perhaps because it was originally not shown to this area, but he demanded nonetheless an apology from those who had produced it. Governor Volpe, who saw it two days ago, reacted rather differently; he asked Police Commissioner Sullivan to conduct a thorough investigation of his department.

Clearly, if there is sufficient evidence of police corruption to disgust the Governor and to send the city into a stew, Cardinal Cushing's defense can be dismissed as an irrational view of a question on which he simply was not qualified to pronounce. Unfortunately, the Cardinal has done more than speak out of turn; like the Protestant ministers who shouted loudly that police corruption is intolerable, he has helped to revive Boston's saddest and oldest religiously based controversy. The prelate and the policeman in his diocese can still remember when signs were hung announcing that "Drunken Irish need not apply." Their memories are even more vivid and bitter when, seemingly without discrimination, their officals are called corrupt and vicious. Cardinal Cushing's wrath is easy to understand, but his resurrection of religious distrust will only throw a stranglehold on genuine and rational attempts to clean up the city.