The legal saga regarding the Philadelphia Catholic Church sex-abuse scandal continued Monday as a prosecutor said in her opening statement she would prove that a priest and a Catholic school teacher sexually assaulted the same middle-school altar server in separate incidents.

Defendants Bernard Shero and the Rev. Charles Engelhardt had their cases severed from the trial of Monsignor William J. Lynn, the first Catholic Church official in the country to be charged with harming sexual-abuse victims whose abuse he was responsible for investigating.