The driver of a dump truck that struck and killed an Arlington mother this year was found guilty of a traffic infraction Thursday and given six days in jail and a $100 fine.

Marvin Valladares, 33, pleaded not guilty to the charge of “failure to devote full time & attention to driving,” Assistant Commonwealth’s Attorney Jay Burkholder said, but acknowledged that the facts and evidence were sufficient to find him guilty.

Valladares was driving his truck down North Little Falls Road in Arlington on Feb. 24 just as Jennifer Lawson, a 39-year-old mother of three, was putting her youngest child into a car seat. The step on the side of his truck hit the sliding door of Lawson’s minivan, Burkholder said, causing the door to strike Lawson and fatally injure her. She died of her injuries at Inova Fairfax Hospital.

Police described the collision as a “tragic accident,” but found that Valladares was driving slightly too far to the right. The step on his truck, Burkholder said, was just over the line that separates the roadway from parked cars.

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