Well, hardly any accidents are caused by faulty vehicles. I think it's a strategy to let them check for drugs and alcohol and other illegal stuff in your vehicle (weapons, in the USA where I'm from). Accidents are usually caused by bad driving.
I was pulled over here in my 109 once, for inspection, and I was petrified. I had never been pulled over by police before. Luckily Mr. Lucas showed up instead of Dr. Prince of Darkness, and all the indicators, etc. worked. I was so nervous that I even gave the policeman my residency permit instead of my driver's license.
What I think they should do, more, is force drivers to pass a theory test at regular intervals, for those whose test was decades ago and who dont know the new rules, markings, etc.
The farmers here would say that the police need to check if people can reverse to let a tractor by on a narrow lane. People drop off the side of the road, crash into hedges, etc. because they haven't practiced reversing in years. It's pretty fun to watch sometimes!
Jeremy