From the Associated Press — A law firm says about 20 students at a Michigan high school where four students were killed in a mass shooting say their constitutional rights to safety and education have been violated. A federal lawsuit being filed Friday calls for changes to ensure security at Oxford High School near Detroit. The suit names the Oxford Community School District, its former superintendent and several other officials. It seeks an independent review and policy changes, including increased transparency and communication from the district. The Associated Press sent an email seeking comment from the district. Ethan Crumbley has been charged with murder and terrorism in the November 30 shootings that also left six other students and a teacher wounded.