The Prisons and Probation Ombudsman (PPO) can investigate issues about the way you have been treated.

The PPO may be able to look at your complaint if you are:
  • a prisoner serving a prison sentence (including both public and privately run prisons)
  • a prisoner on remand
  • a young person held in a secure training centre or YOI 
  • a detainee held in an immigration removal centre
  • under supervision by the probation services (including Community Rehabilitation Companies)
  • living in a probation approved premises 
  • complaining about escorts to or from these establishments
  • recently released and complaining about a problem that occurred while you were detained.

This includes decisions and actions (including failures or refusals to act) relating to the management, supervision, care and treatment of those people listed above. You should always complain directly to the provider of the service in the first instance to try to get the problem resolved.

If your complaint is not resolved or you are not happy with the way your complaint is dealt with, then you can submit your complaint to the PPO. 

Before you complain to the Ombudsman, you must have gone through all the internal process or they will be unable to investigate your complaint.

See full details here