The Constitution endows Congress with broad powers of investigation to aid the legislative process. But recent years have seen this power abused with increasing frequency as witnesses are coerced and browbeaten under the burning arcs of television spotlights. Last night, Law School Dean Erwin Griswold added his great influence to that of the many public figures who sharply oppose such committee practices. "If a man has done wrong, he should be punished," he said, "but the evidence against him should be produced and evaluated by a proper court in a fair trial."

Earlier this week, a New York State legislative committee heard a plan designed to curb misuses of the investigator power. Offered by the state bar association, the code establishes rigid procedural rules for investigating committees, assuring witnesses a chance to defend themselves from a one way stream of accusations.

The association's code would grant the witness the right of counsel, cross-examination of his accusers, and subpoena power for securing witnesses in his behalf. To prevent unfair publicity, the code would force committees to hold back charges until the witness has a chance to answer them, and allow those accused to read explanatory statements into the records. A final check on committee irresponsibility is the code's insistence that each group state the scope of its investigation and then stay within these set limits.

Admittedly, these restrictions may slow committee action, and, in rare cases, subject investigators to longwinded protests. Put into effect, however, they will not only protect the witness, but also transform reckless inquisition into constructive investigation.

Such provisions are not new. The House Judiciary Subcommittee has operated successfully under similar rules in its investigation of tax cases. But the importance of the New York proposals lies in their application to investigations of communism. Contact with this emotion-charged sphere will lend the code wide publicity.

Justice Brandeis once called the states a laboratory for legislation. New York's proposed code of fair investigative practices is just the kind of experiment the Justice must have had in mind. If passed, it can provide a working model for Congress and the states to examine, and perhaps, to adopt.