Washington (AFP) – The US Supreme Court opened the door to the expansion of religion in public schools Monday when conservative justices backed a Christian high school football coach who lost his job after leading his team in post-game prayers on the field. The court voted 6-3 along conservative-liberal lines that Joe Kennedy, a coach for Bremerton High School in Washington state, was protected by the US constitution’s guarantee of religious freedom when in 2015 he ignored supervisors’ warnings and continued to pray after the games. The high-profile case pitted backers of the principles of fre…