A Framingham man was sentenced today to life in prison for shooting a police officer who was chasing him after the armed robbery of a taxi driver. Sahr Josiah, 24, was found guilty earlier this month of charges including armed robbery, armed assault with intent to murder, possession of a firearm as an armed career criminal, and assault and battery with a dangerous weapon. Middlesex Superior Court Judge Diane Kottmyer handed down the maximum punishment on all counts. In April 2009, Josiah was being chased following the armed robbery of a taxi driver in Framingham. As police chased him, Josiah opened fire and shot Framingham Police Officer Phillip Hurton, Middlesex prosecutors said. Hurton was shot in the wrist and face.