FORT WORTH — A 30-year-old man with several prior convictions was sentenced to 99 years in prison Friday for shooting the father of his new girlfriend’s children 12 times on Thanksgiving Day last year.Artis Leon Polk Jr., who had been on parole for six months, bought a semiautomatic assault rifle off the streets in Dallas two days before he killed 23-year-old Charles Knighten on Nov. 22, 2012, prosecutors said.Jurors in state District Judge Ruben Gonzalez’s court also sentenced Polk to 20 years for unlawful possession of a firearm by a felon. Gonzalez ordered the two sentences to run concurrently, according to a news release from the Tarrant County district attorney’s office.During the trial this week, prosecutors Lloyd Whelchel and Kim D’Avignon presented evidence that Knighten, with his mother and stepfather, stopped to pick up his two children to spend time together on the holiday. The children lived with their mother at an apartment in the 500 block of Ridings Place in north Arlington. Polk had recently moved in with the woman.Knighten, Polk and the woman got into an argument, and Knighten pulled out a BB gun but was persuaded to put it away. Then Polk came out of the apartment with the rifle and shot Knighten 12 times, including three times in the back, the news release said. As Knighten lay dying on the sidewalk, Polk pulled the BB gun out of Knighten’s pocket and fled. He returned later and was arrested.Polk testified that he shot Knighten in self-defense. Polk’s criminal record includes convictions for drug possession, vehicle theft, burglary and aggravated robbery.
Mitch Mitchell, 817-390-7752 Twitter: @mitchmitchel3