A D.C. Superior Court jury yesterday convicted a Bladensburg man of murdering a woman acquaintance in a case where the crucial evidence was a speeding ticket the man got within minutes of the shooting.

Raymond McCoy Robertson, 50, shot Mary Elizabeth Jackson, 37, a Metro supervisor and mother of six, because he was upset that she wanted to end their relationship, the prosecution charged in the case.

The shooting occurred about 8:05 p.m. on Jan. 14 near Deleware Avenue and I Street SW in the District when Robertson, driving one car, pulled alongside Jackson's car. Less than 10 minutes later, a police officer stopped Robertson near the murder scene and gave him a speeding ticket, according to Assistant U.S. Attorney J. B. Stephens. Robertson was released after he got the ticket because police were not aware of the murder at the time he was stopped, according to Stephens. Robertson later told police that he was at home in Maryland when te shooting took place.

During the trial, Stephens argued that the speeding ticket proved that Robertson's alibi was false.

After Jackson was shot, the car she was driving spun out of control and rammed into a church where 300 people were attending a revival meeting. No one at the church was injured.

Robertson is facing a prison sentence of 20 years to life. Chief Superior Court Judge H. Carl Moultrie is scheduled to sentence him Dec. 4.