Should a presidential pardon be granted to key figures in the Iran-Contra scandal?

After providing a sensible answer this week to that long-pending question, President Reagan backed off and left confusion in his wake.In response to a question from a syndicated columnist, Mr. Reagan wisely declared that his policy was not to pardon anyone until after they have been convicted.

That stance - confirmed by White House spokesman Marlin Fitzwater - seemed to rule out a Reagan pardon for former national security adviser John Poindexter and former National Security Council aide Oliver North, since their trials likely won't be completed until Reagan leaves office.

But the very next day, when asked if he had ruled out pardons for Poindexter and North, the President replied with a firm "no" without elaborating.

He should have stuck by his first response.

Why? Because presidents ordinarily issue pardons only to those who have been convicted, exhausted legal appeals, and asked for clemency. And because a pre-trial pardon would short-circuit the legal system and possibly do an injustice to Poindexter and North, who may not be convicted of anything.

Likewise, it would put Mr. Reagan in the position of repudiating his promise to do "everything in my power to make the facts known" in the Iran-Contra affair.

A pardon before the November elections would be bound to bring on a backlash at the polls, and a pardon afterward would look like an effort to avoid having to answer to the public.

Moreover, a pardon would leave a stain on the Reagan presidency by creating the impression that Poindexter and North were being rewarded for taking the rap on the diversion of funds and stopping the buck just outside the Oval Office.

Even if Poindexter and North are convicted, it still could be shown that they did so for honorable motives, however misguided, rather than for personal gain. If so, a case could be made for treating them with mercy.

But the time to consider a pardon is after all the facts are in, not before it's clear exactly what would be pardoned. By that time, Ronald Reagan should have left office.