Montgomery County has often touted itself as among the "best run" photo enforcement program not just in Maryland, but in the nation. A new investigation by the Maryland Drivers Alliance shows how one factor behind the county's ability to generate $23,408,609 in annual revenue is that it has set yellow times below the legal minimum required by both state and federal law.

On September 21, a camera operated by Xerox photographed motorist Peggy Lucero while she was turning left at the intersection of Georgia Avenue and Seminary road. When the flash went off, she knew something was wrong. She believed she made the light. It turns out, she missed it by about six-tenths of a second. The reason she miscalculated was that the signal was timed six-tenths of a second shorter than state law requires.

Lucero's ticket shows the yellow signal offered just 2.9 seconds of warning, which is less than the 3.0 second minimum mandated under federal law. It is also lower than the stricter legal standards in effect in Maryland since May 2015.

"The State Highway Administration does not use yellow change intervals lower than 3.5 seconds," the agency explains in its traffic signal guidelines.

Lucero contacted the motorist rights group about the ticket she received, and the group filed a public records request for the signal timing at the intersection. The documents confirmed the location failed to meet state standards. At another left-turn approach at the same intersection, the left turn signal is correctly set at 4.0 seconds.

The Maryland Drivers Alliance filed another public records request for yellow timing data from individual citations so that it could determine how many violations were caused by the shortened yellow times. County officials refused to disclose this public data unless the group wrote the county a check for $19,000.

"They obviously know nobody could pay such a large fee for this kind of data," Maryland Driver's Alliance spokesman Ron Ely told TheNewspaper. "Apparently they don't want anyone who might be critical of their program to obtain enough data to conduct any sort of analysis."

A fraction of a second difference in yellow time can have a significant influence on the number of red light camera citations issued. The majority of straight-through red light "violations" happen when a driver misjudges the end of the yellow light by less than 0.25 seconds -- literally the blink of an eye (view Texas Transportation Institute (TTI) chart). In most cases, a yellow shortened by one second can increase the number of tickets issued by 110 percent, according to TTI (view report).