The candidate: State Rep. Dwight Evans, Democrat

The ad: "Right Now," a 30-second spot running on Philadelphia broadcast and cable channels.

Producer: Murphy Putnam Media, Alexandria, Va.

Script and images: Black-and-white mug shots of businessman Tom Knox, Evans, and U.S. Rep. Chaka Fattah are superimposed on the Philadelphia skyline. "Major differences on crime," an announcer says. "Tom Knox has no record fighting crime." The Knox mug shot slides to the right. "And Chaka Fattah says there's nothing a mayor can do to immediately reduce the murder rate." Fattah's mug shot is emphasized. "Dwight Evans thinks a mayor has to do something." The man is shown in full color walking with people and speaking outside City Hall. "He lowered crime in West Oak Lane and made it a model for the city. He can lower crime in all of Philadelphia." Evans is shown walking with police officers. Narrator: "Five hundred more police in our neighborhoods, trace guns found on juveniles, and closely supervise those on parole or probation." At the end, the skyline appears and Evans fills the screen. "Dwight Evans for Mayor."

Analysis: It is true that Knox has no crime-fighting record as a public official. The Fattah quote is accurate. He was responding honestly to a direct question from a student at a February forum, saying no mayor could reduce homicides immediately. Based on some statistics, crime is down in Evans' district, but his role in that is debatable. - Thomas Fitzgerald