Hypotheticals

Picture the scene, a serial killer is on the loose, he's (for it is likely to be a he) is killing people very often. The police have suspects, but nothing firm. Every day this killer is on the loose more people are threatened, but the investigation is proving long and complex. Should we be able to lock these suspects up for 42 days? It's a hypothetical you say.

But maybe we should put in a provision in case it becomes unhypothetical?