Roger Graef is one of the country's most distinguished documentary-makers, whose 1982 series Police is credited with changing how the police conduct rape investigations. Patrick Forbes is the producer behind The Force, Channel 4's acclaimed behind-the-scenes look at police investigations in Hampshire.
The two men shared their insights at the Sheffield Documentary Festival about how they gained the trust of the police to present an uncompromising investigations into how criminal investigations really work.
Forbes said The Force originated from a suggestion by a senior Hampshire police officer to film the true workings of the police force.
"They wanted some understanding of what they did," he said. "They felt cop shows on TV give a completely distorted picture of what actually goes on."
A deal was struck to give Forbes's team full access.
"To get reality you have to tough it out and insist on total access and that they will not mess you around and say X or Y is sensitive," he said.
Graef said that back in 1982 the police had also wanted to see themselves shown in a more accurate light.
"The version of police fiction in the 70s was the same misrepresentation of what police work was really like," he said.
"Corruption scandals in the late 70s, particularly around Scotland Yard, had given an extra distortion.
"You had the fictional version where the cops always get their man by the commercial break, and the tabloid version where they were all bent – neither of these were true."
He said trust was won by spending time with the subjects of a documentary.
"You have to be there for long enough, hang out with them, drink with them, don't hide behind your professionalism."
He said to reassure people they would be fairly treated, it was good to remind them at the start of filming that the film-makers' next project would rely on their endorsement.
Forbes said it was essential that a programme be supported by a senior member of the police force being portrayed.
"Unless you have an advocate inside the force, you are completely sunk," he said. "It wasn't a question of me talking to them, it was him [the senior officer] talking to them."
Both men stressed the need to be given time to make programmes of quality – The Force took three and a half years to be completed.
"It's tough to do these things," said Forbes. "You do have to hang out for years to get the result and you have mouths to feed and mortgages to pay. We are all looking for a quick fix."
Graef said commissioners had to be patient. "You need patrons, actual people with the balls to give you space and time."
