Three weeks after the event, nobody is any clearer about exactly what happened in Ferguson on the day that police officer Darren Wilson shot 18-year old Michael Brown. If brought before the court, Wilson is likely to claim self-defence, but varying witness accounts make it difficult to ascertain exactly what happened during the fateful minutes that spawned weeks of protest and civil unrest.

Here's one thing that might help: in response to the shooting, Ferguson police now wear body cameras to record their interactions with the public. The Ferguson force trialled the technology during protests on Saturday, with cameras clipped to their uniforms to capture the behaviour of protesters and policemen present.

Speaking to St Louis Post-Dispatch, Ferguson chief of police Tom Jackson said: "They are really enjoying them (the cameras). They are trying to get used to using them."

The cameras have been made by the video surveillance company Safety Vision. In a statement on its site the company said: "The city of Ferguson has gone through an unfortunate series of events and Safety Vision body cameras and flashlight DVR will assist in capturing prima facie evidence for investigations involving vandalism, looting, and shots fired." 

Of course, what it doesn't mention is that the cameras will also be able to record incidents of police brutality – such as an officer shooting an unarmed teenager six times. 

America is not the only country looking to integrate wearable surveillance technology into the everyday policing of its citizens; the UK want to do it too. There was public pressure for Metropolitan Police officers to wear cameras after the killing of Mark Duggan in 2011. A trial earlier this year saw 500 cameras handed out to officers across ten London boroughs.

Some critics say that the cameras are yet another encroachment on privacy – a visible example of a constantly surveilled world that might actually deter people from approaching a police oficer. Others say that the cameras will enforce good behaviour on both "sides", arguing that incidents of police wrongdoing may drop and criminals will have a heightened awareness that are being watched and recorded when in the presence of an officer.

What do you think? Should all police officers wear a camera?