Bias is prejudice in favour of or against one thing, person or group compared with another, especially in a way considered to be unfair. Film directors use bias when making a film because they want the viewers to have particular feelings towards the situation or one or more characters, e.g. sympathize with them. I think Peter Medak wanted to make this film because he thought that a great miscarriage of justice had been carried out and wanted the world to feel the way he did by making a film version of the true story that is biased in favour of...
a young man who needed help more than hanging.

The scenes on the roof also lead for the viewer feeling sorry for Bentley because he is shown weak and vulnerable- when one of the officers grabbed hold of him he did not make any attempts to get away, suggesting that he didn't want to get into trouble and didn't mean to cause any intentionally. Derek also made remarks regarding his and the officers' safety which show the caring nature. Not many people would worry about the safety of anyone else, especially the police officers in this situation.