How long you can be held in custody. The police can hold you for up to 24 hours before they have to charge you with a crime or release you.They can apply to hold you for up to 36 or 96 hours if you’re suspected of a serious crime, eg murder. You can be held without charge for up to 14 days If you’re arrested under the Terrorism Act.hey can apply to hold you for up to 36 or 96 hours if you’re suspected of a serious crime, eg murder. You can be held without charge for up to 14 days If you’re arrested under the Terrorism Act.