Between The Lines BBC4
This series starts tonight on BBC4. IIRC, it's from the early 1990s and is a forerunner to Line Of Duty. BTL stars Neil Pearson as DCI Tony Clark, Tom Georgeson as DI Harry Naylor and Siobhan Redmond as DS Maureen Connell.
I remember this programme only vaguely. We used to have it videotaped for us because we lived in Rome when it was first shown.
https://www.bbc.co.uk/programmes/m000tpzg