IT'S RARE to find a government data bank that should be gathering and sending out more, not less, information about citizens. The Department of Transportation, though, does have a system that is not being used well enough. It's the National Driver Register, and its effectiveness could make a life-or-death difference on the nation's roads.

The driver register helps the states exchange information on people whose driving privileges have been suspended or revoked. The aim is to prevent bad drivers, after losing one license, from hopping across state lines to get a new permit and keep right on driving as recklessly as before. The National Highway Users Association cites as a graphic example a truck driver who ran up over 25 moving violations and some accidents, had his North Carolina license suspended five times, then got a Florida license and started collecting violations there. Neither state found out about the other record until the driver had hit a parked school bus near Lynchburg, killing three children.

The clearinghouse does flag daily about 750 scofflaws who have lose one license and applied for a new one elsewhere. But some states do not use this service. California, for instance, prefers to get more detailed driving records directly from states in which applicants acknowledge having been licensed before. Few applicants lie about their records, one California official says. Other states are less trusting and see more potential value in the driver register, but use sporadically because its reliance on the mail makes it too slow. And some states hand out at least temporary permits without making any real checks at all.

No clearinghouse can answer all the needs of all the states or do much for those that pass out driver's licenses as casually as highway maps. The driver register could be made more swift and useful, though, by linking it with NLETS, a nationwide telecommunications network operated by a consortium of state law-enforcement agencies. While this would have to be planned and phased in carefully, it does sound like a promising approach. After all, this is one data bank whose information should be shared, accurately and promptly. It's a good way to flag down the dangerous drivers who are a menace to everyone else.