Sen. Harrison Williams Jr.'s fellow Democrat, Sen. Howell Heflin, has pointed a way of salvaging something for the American nation from Mr. Williams's Abscam disgrace. It is to recognize more sharply than before that there are some things a person worthy of the high calling of senator of the United States simply cannot be tempted to do. This is in welcome contrast with what another fellow Democrat, Sen. Daniel Inouye said in serving as Mr. Williams's defender: that the FBI in its Abscam operation ''proved that perhaps all of us are ultimately corruptible.'' It's only a step from the latter view to Mr. Williams's brazen insistence that he did nothing wrong.
There is no question here of rushing to judgment, of failing to consider a man innocent until proved guilty. Mr. Williams has been proved guilty and sentenced in a federal court for offering to use his office for personal gain. The Senate Ethics Committee found his conduct ''ethically repugnant'' and tending to bring the Senate into dishonor and disrepute. This week the whole Senate has been debating his expulsion.
The possibility of exculpatory evidence cannot be foreclosed. Some senators are calling for an investigation of the FBI for possible abuse of power in staging the Abscam opportunities for public figures to commit crimes. This would help to clear the air and ensure that any abuses not be repeated.
But Senator Heflin, a former chief justice of Alabama's supreme court, went to the heart of the matter, the senatorial integrity that ought to be its own armor against corruption. Any misconduct by the government would have no bearing on judging appropriate conduct for a senator. Even assuming there was entrapment in the videotaped Abscam meetings, he told the Senate:
''If a member of this body really knows right from wrong, if he or she truly cares about the integrity of this institution, then that member would not hesitate for a moment to get up and walk -- walk away from sleazy characters swearing like sailors; walk away from talk about sheiks and deals and hiding interests and protection and concealment . . . walk away, in other words, from obvious impropriety.''
Americans can hardly accept a lesser standard for their public servants, or for themselves.