Factual error: Everyone, including other police officers, addresses the detectives as "Detective" rather than using their ranks of "Inspector" or "Sergeant" as they actually would.
Factual error: DI Renton is a Metropolitan Police officer 'parachuted' into Kent to solve a big case. This hasn't happened for many decades. Local police forces investigate their own crimes without help from the Met.
Factual error: The series is based in the east-facing Deal, Kent. Even if this is not explicitly mentioned, there are visual references to the Thanet and Dover Police. So how can you have repeated sea view sunsets? Either that or they are having wine for breakfast at the breakfast table. The sun rises in the east and Deal enjoys a beautiful sunrise.