An 81-year-old man convicted of killing his ex-girlfriend's boss in a shooting at a synagogue was sentenced Thursday to life in prison. Marc Benayer was convicted of first-degree murder last week in the shooting death of Jonathan Samuels. Samuels was shot in October 2005 as he left Chad Weltman Synagogue near Boca Raton after a Rosh Hashana service. He died in July 2006. Benayer, who acted as his own lawyer, had claimed the shooting was an accident. During his sentencing hearing, he claimed that Samuels' death was due to a surgical mistake, not the shooting.