Continuity mistake: In Episode 9 of Season 1, Roy Galloway sells his Ford Cortina to a car dealer. He has to wait a day for paperwork and drives away in a Vauxhall Cavalier A242 GLO. He revisits the car dealer, and his Cortina is up for sale on the forecourt for £1495, then drives away in the Cavalier. However, in the next episode, he is back to driving the same Ford Cortina. Again, you don't see the registration, but in Episode 11, it's visible: BBH 469T, the same as in the pilot episode. (00:20:36 - 00:22:20)
Continuity mistake: Season 19, Episode 159. When Des Taviner flips and drives the area car wildly around an industrial estate and into a gas storage facility, you can see that during the sequence the Vauxhall Vectra he is driving starts off as a Y registration, then changes for several shots to a P registration, and then finally back to a Y registration when it blows up inside the building.
Continuity mistake: In the 07-02-08 episode, in the riot scene, after the riot police are told to close in on the rioters, and you see an overhead shot of them moving in. They are within touching distance of the rioters. In the next shot from behind the rioters, they are now quite a long way from the police.