There have been recent incidents locally of dangerous driving, if you see it or think that a driver may be a danger, (extracted from RAC website)
Dangerous driving offences include the most serious motoring charges on UK roads. If you spot someone driving dangerously, then you can help improve road safety by reporting it to the police.
The RAC help you understand what dangerous driving involves, its punishments and how you can report other motorists for endangering others.