[JURIST] The US Court of Appeals for the Third Circuit [official website] on Tuesday ordered [opinion, PDF] a new sentencing hearing for Mumia Abu-Jamal [Philadelphia Inquirer backgrounder], a former member of the Black Panthers who was convicted and sentenced to death for killing a police officer in Philadelphia in 1981. The three-judge panel concluded that the jury that sentenced Abu-Jamal to death was given an improper jury instruction regarding the use of mitigating factors. According to the court, the instructions…