In case you missed it, the BBC's Inside Out East programme on bad professional drivers, screened last night, is available on iPlayer for the next month.
The programme showcases how cyclists and drivers are using action cameras to catch professional drivers who drive badly.
Presenter David Whiteley meets Dave Sherry, a cyclist and bus driver from Harlow, who posts footage on YouTube of lorry, van and bus drivers whom he believes are driving irresponsibly.
Sherry's clips frequently come to the attention of drivers' employers who are rarely happy to have their name associated with poor driving.
In 2013, Sherry's footage of a bus driver using a mobile phone led to the driver being sacked.
Sherry also sends the worst examples to the police.
Asked by the presenter if what he does isn't vigilantism, Sherry points out that he doesn't take the law into his own hands. "I just report it, but I'm very effective in the way I report it," he says.
How effective? He claims his footage has resulted in around 50 convictions, which probably makes him the most effective citizen traffic cop in the UK.