What are the three reasons usually given for introducing police body-worn cameras (body cams)?

They provide evidence in disputed police-citizen encounters, they deter misconduct on both sides, and as a result they increase citizens' trust in and cooperation with the police.

According to Thomsen (2020), the case for body cams rests on three expected effects:

1. Evidence: recordings provide useful evidence in potentially controversial interactions between police and citizens.
2. Deterrence: they discourage unwanted behaviour, above all excessive force by the police, but also attacks on and harassment of officers, unjustified complaints and bribery attempts.
3. Trust: partly as a result of the first two effects, they increase citizens' trust in the police and their willingness to cooperate.

The camera is meant to watch both sides. That is why some officers welcome it as protection and others resent it as control (see the next card).

Go deeper:

• Wikipedia: Body camera — police body cams, their use and the evidence on their effects.