TODAY'S REGIONAL winner in the best-exercise-in-self-defeat category comes from Metro, where board chairman Joseph Alexander has come up with a new policy for five station parking lots in Virginia. Mr. Alexander, who also is a Fairfax County supervisor, says he is asking Metro to prohibit parking for more than 24 hours at the Huntington, Vienna, Dunn Loring, West Falls Church and East Falls Church stations. The idea is to stop air travelers from leaving their cars at the Metro lots and thus avoiding parking fees at National Airport. The penalties would be stiff: cars left more than 24 hours would draw $25 tickets and after 36 hours would be towed. This presumably would open spaces for the daily commuters at these lots, which are almost always filled by 7 a.m. Clever, no?

No. Even if efficient policing could separate the long-timers from the dailies on the lots, the ultimate effect would be to send those airport-bound travelers all the way down the roads to National, where the lots are routinely jammed most weekday mornings anyway. Above all, the policy would drive away people who actually want to use Metro. Given all the fanfare focused on winning people over to Metro, the last thing the agency should do is punish those who take the advice.

Logic -- which on this point apparently escaped the planners long ago -- calls for much bigger parking lots. Those little postage-stamp lots out there now were obsolete before they appeared. People who try to use Metrorail need to getto Metrorail -- and it has to be a convenientand reliable connection. Hitting Metro users with $25 fines and/or tow charges just because they may be taking airplanes as well as subways is foolish.