May police officers detain and search all members of a group on grounds that the behavior of one person was suspicious, and is trial counsel constitutionally ineffective when failing to move to suppress evidence gathered during an investigative stop made without individualized reasonable suspicion?

Cornell’s trial attorney at his m urder trial failed to m ove to suppress evidence on grounds that Cornell was detained without reasonable suspicion. The questions presented are” 1. May police officers detain and search all m embers of group on grounds that the behavior of one person was suspicious? 2. Is trial counsel constitutionally ineffective when he fails to m ove to suppress evidence gathered during an investigative stop m ade without individualized reasonable suspicion?