It's easy to imagine after watching a few seasons of police procedurals on TV that you basically get criminal procedure, especially arrests. But you probably don't because even lawyers who practice in court every day have to check legal texts when preparing to challenge an arrest.
But understanding arrest is important for all because it can happen to anyone, even those of us who try hard to avoid trouble. So let's consider arrests generally and arrest warrants in particular. When do police need a warrant and what must it specify?