When necessary, applications to court for emergency remedies can be made. (vardags.com)
Even then, their DNA samples / profiles are only retained for a period of up to three years, which can be extended on application to a court. (newlawjournal.co.uk)
This was following several applications to the court which simply resulted in them moving to another site within the town, or even back to the original sight. (hughjames.com)