 The Terrorism Act 2006 in the United Kingdom lengthened the 14-day limit for detention without an arrest warrant or an indictment from the Terrorism Act 2000 to 28 days.A controversial Government proposal for an extension to 90 days was rejected by the House of Commons.English criminal law requires the detainer/arrestor to have reasonable grounds to suspect (reasonable suspicion) when detaining (or arresting) someone.