If your automobile is licensed in the District of Columbia, be warned: before you turn the ignition key, check your license tags. Your failure could cost you $100, as it almost cost my colleague Karlyn Barker the other day.

She had not noticed that the "July" expiration stickers on both her front and rear tags, affixed last summer, had fallen off. But a ticket-writer did. Either there was not enough stickum on the stickers, or they worked loose from the raised letters of Barker's Bicentennial tags, issued in 1976. (Under D.C. law, the "July" stickers must be placed at the lower left corner of the plates, atop the raised letters. Newer plates have a flat surface in that area.)

Certain that her case was solid, Barker went Thursday to the D.C. Bureau of Traffic Adjudication and found it nearly mobbed by people seeking to modify the newly increased city traffic fines. Many got off free.

Barker, who did not, reports: "I got the fine reduced to $10, but was lectured on my civic responsibility to report lost or stolen stickers in case someone else is using them. I would have if I'd known. But, as I told the hearing officer, it's not like brushing your teeth. I don't look at my license plate every day; I don't even drive my car every day."