THE FIFTH AMENDMENT'S ban against compulsory self-incrimination is the keystone of American justice. So we were delighted the other day when the Supreme Court refused to weaken it. By a vote of 7 to 1, the Court struck down a New York law that removed from office any official of a political party who claimed his rights under that amendment before a grand jury. The opinion by Chief Justice Burger said that government cannot penalize people solely because they exercise this right, which the Constitution guarantees to them.

Perhaps the most important aspect of the decision is that it is in line with the philosophy of decisions made a decade ago by the Warren Court. In this one aspect of the Bill of Rights, at least, the present members of the Court show no inclination to strip away the protections for individual rights that were built so carefully during the 1950s and 1960s. It is unfortunate that the same cannot be said about other constitutional guarantees, particularly the one against unreasonable searches, which the present Court seems intent upon narrowing as much as it can.

It is quite true, as the state of New York argued in this recent case, that the protections contained in the Bill of Rights sometime make the task of fighting crime and corruption difficult. In this instance, the state wanted the testimony of Patrick J. Cunningham, the Bronx Democratic chairman, about corruption in that borough. It could have compelled him to give that testimony, the Supreme Court said, but only if it had granted him immunity from prosecution. But if it didn't want to grant that immunity, it couldn't penalize him for refusing to incriminate himself.The choice that a state must sometimes make in situations like this is between compelling officials to account for their actions and prosecuting them; it can't do both.

While that may create a dilemma for those seeking out political corruption, it is the kind of dilemma that is inevitable if the Fifth Amendment is to retain its vitality. It says that government cannot compel self-incrimination, and the Court is quite correct in not allowing that right to be overridden by other governmental interests - even the vital one of preserving confidence in the integrity of the political process.