ON THE OFF chance you weren't paying attention to yesterday's paper, we reprint the lead paragraph of a UPI story pointing to a mighty breakthrough in the psychiatric art of prisoner-rehabiliation. Here is is:

CHICAGO, Dec 12 -- Psychiatrists say a man who admitted beheading his girlfriend and mailing her toes to former president Gerald R. Ford and former Soviet premier Alexei Kosygin can be safely freed from a mental hospital.

How about that, rehabilitation fans? In order to appreciate the wonder of this cure, you need also to know what the poor unfortunate who committed these infractions (and which of us is perfect?) was himself committed to a mental health center only two years ago. Now someone is contending he is fit to get out, the "insanity," by reason of which he was found innocent of the murder in the first place, having evidently been dispelled or at least made tame.

The prosecutors in this case are apparently being perfectly terrible reactionaries about it, even to the extent of using the inflammatory unclinical and unenlightened language to describe their feelings. "The doctors are nutty," one said to the UPI reporter. This prosecutor could conceivably have been hung up on the fact that in addition to mailing all those toes around the world, the inmate in question had also mailed the head of his formerly beloved to her brother -- said head having been "recovered at a post office," which only goes to show you that not only our criminal justice system, but also our postal system is working.

So this is a real good news story. And for that reason we hate to mar it with a negative, doubting note. It's just that we ourselves have the tiniest little nagging apprehension about the release. What exactly, we find ourselves wondering, does a person have to do to get pronounced unfit to be out, and how many of these others, the relatively safe ones who just go on an innocent extremities-mailing binge, are already riding the bus and standing in the checkout line?

Assuming there are other nervous Nellies like ourselves, we suggest, to be constructive about it, that a safe and fair solution would be for the particular doctors who have reached this compassionate decision to take legal, moral and financial responsibility for and custody of the released inmate themselves if their counsel is followed. That way he could just move in with one of them and provide an inspiring daily reminder of their curative powers. New policy: return to sender.