Has this ever actually happened or is it just a movie cliche? It seems like it would be a very chancy way of killing somebody. For one thing, how do you make sure that the brakes fail at a critical moment? For another, many people would have the presence of mind to use the parking brake or throw the car into gear.
Most likey fiction for the reasons you state.
A claim of a stuck accelerator was in the news not too long ago.
A stuck accelerator is very unlikey to nearly impossible in my estimation.
The claims of a “sticking gas pedal” are more likely driver error such as the driver runing into a crowd of people and injuring same.
I can’t imagine this as a practical method of killing someone, for just the reasons you mention. If you puched a hole in the brake lines (so the brake fluid leaked out) you’d have to do it immediately before the person drove off, or else they’d probably notice the loss of brakes as they were backing out of the driveway or something. Even if you did manage to cause a major crash, the victim will probably survive if he’s wearing his seatbelt. Basically, you’d need an extremely contrived situation for this technique to have any realistic hope of success. Like the victim is a major speed demon who commutes to work along twisty mountain roads high in the Rockies or something.
I’m sure it would be possible to engineer a fault that only caused loss of fluid under pressure; i.e. when the brake pedal was pressed; even so, this woould have to happen at a critical moment in order to cause a fatal crash and that would be very difficult to orchestrate.
I did hear a story about a Frenchman who attempted to murder his wife by tampering with the brake pipes, but he accidentally cut a pipe belonging to the fluid suspension system (the car was one of those old Citroens with the pressurised/pumped suspension), causing the car to fall on him, crushing him to death. Dunno if it’s true.
Movies have taught us a coke can in the drivers area will always get stuck under the break and cause an accident so why bother climbing under the car.
As a sure fire way to kill someone its a bad idea. If you just kinda want to kill someone and have years to pull it off cutting a break line could yeild results on a poor driver in an older car. It is unlikely anyone would notice the break line was cut. Cops don’t tend to investigate accidenets beyond who’s fault it is. Getting the wreck out of the way is a bit more important.
I thought there were supposed to be some sort of rubber bumpers for the suspension to ride on in the event of a leak, so perhaps he would have had room to squirm out.
In any case, I agree with the above. I’d been thinking about it recently (not sure why) and it occured to me that the only way to do it would be to have a small detonator on the brake lines so that you could do away with the brakes at an opportune moment. Otherwise the leaking of fluid would be too noticeable, moving off out of your driveway for example or in traffic.
Hoser, the parking brake never worked!
Maybe urban legend, but technicaly it is not far off.
I am the proud owner of a 1973 Citroen DS and I know a few things about these cars. When the engine is turned off, the car lowers all the way down and there’s probably less than a couple of inches of ground clearance. But when the engine is turned on and the suspension is set at the highest level there’s enough ground clearance for a person of average build to crawl under the car.
Maybe the good Frenchman decided to crawl under the car while the suspension was raised and cut the brake lines.
But…
These cars share the same fluid (LHM) for suspension, brakes and power steering. It comes from a single reservoir (always painted green) inside the engine compartment. So essentially, if you have a severed brake line you also lose suspension and power steering. And since the suspension won’t lose pressure imediately, the car will start lowering rather slowly which will ensure a slow and agonizing death. :eek:
Having had completely failed brakes and intermitantly failing brakes on my old VW Golf I can say that unless you live on top of a hill, or within yards of the interstate on ramp you really won’t have problems. That something is wrong becomes obvious very quickly after which you can use gears to control speed and hand brake if necessary. Maybe I shouldn’t have done it, but I easily drove the car with failed brakes the few hundred yards to a repair shop.
You couldn’t really time this, but I’d think loosening the bleeder screws would let the person at least get out and driving (in stop and go traffic) before the problem became apparent.
My search-fu is lacking, but I recall reading about a driver whose cruise control broke on the motorway and he couldn’t stop, slow down, or speed up. And he couldn’t turn the engine off for some relevant reason.
If a stuck accelerator is the same thing as a stuck throttle, then this is what killed Adam Petty and Kenny Irwin , both NASCAR drivers who died at the same track in New Hampshire.
This was more feasible decades ago, before dual-circuit brake systems became the norm, but even then it wasn’t as easy as it might sound.
A small hole, such as a nicked metal line or a cracked open bleeder screw, would cause the pedal to sink under pressure, but probably not dramatically - other than (and maybe even with) a panic stop, there would still be a reasonable amount of braking. However, the soft pedal would be noticeable to an alert driver. Eventually, enough fluid could leak out to empty the master cylinder, at which point there would be no braking. If said alert driver had it checked out though, the plan would be thwarted.
A big hole, such as a fully cut metal line or hose, would result in the pedal going to the floor rather quickly. If the vehicle sat for a while between being sabotaged and being driven, the master cylinder could empty, giving no braking from the get-to. Any driver would sense this type of situation on the first pedal stroke, and with an ounce of sense would not drive.
The trick would be to orchestrate a sudden failure that occurred after some normal operation. If one could cut a brake hose to some precise depth where it would hold pressure under moderate braking but rupture with vigorous braking, that might do it. The trick is, what depth? Too far and it bursts on the first pedal stroke. Not far enough and it could go indefinitely. And even if it’s “just right,” it’s still not predictable just when the driver would push hard enough to burst the hose. It’s a pretty sloppy arrangement to cause the desired effect.
With modern dual-circuit systems, one leak will affect part of the braking, but not all of it. On most cars, the systems are split front/rear, but some are split left front/right rear and right front/left rear, and a few in other ways. To disable all braking, one would have to sabotage at least two hoses, and they’d have to be the right two hoses.
The only real advantage to using this method is the hope that it would be written off as an accident. But even that’s not a certainty. There’s a reasonable chance there would be a forensic investigation that would reveal the foul play. All in all, it’s a not a very feasible approach to murder.
Throttles and throttle (accelerator) cables can stick, but it’s rare. Again, it was more likely decades ago with “push” type throttle linkages, as opposed to modern “pull” type throttle cables. Of course, it’s the first thing drivers think of when unintended accerleration occurs, but in 99.99%+ of UA cases, there has been no evidence whatsoever of throttle/cable malfunction. Despite the drivers’ feeling positive their foot was on the brake, almost always logic and whatever evidence exists points squarely to driver error. Unintended acceleration immediately after start-up has been essentially eliminated by interlocks that do not allow shifting out of Park unless the brake is depressed.
It can occur for reasons other than a stuck throttle, too. I have personally been present (but not driving) in two seperate cars (a 90-ish Jetta and a mid-60’s Mercury Comet) that experienced unintended acceleration due to faulty motor mounts causing the engine to move and pull the accelerator cable. In the Comet, I was able to actually look at my buddy’s feet and see that he had them both on the brake pedal and nowhere near the gas while the engine was racing. It was … exciting. 
In the Jetta, the acceleration was brief and we never proved the cause for sure, but we were easily able to open the hood and watch the engine lurch forward as the car started from a stop, and once the motor mounts were replaced, the UA never happened again.
That was the plot of a movie on the “True Movies” (or what ever its called) channel I saw on Sky tv.
I remember reading about a lorry driver having a similar problem, although the police suggested he may have been naughty and did it on purpose. He couldn’t turn off his engine as he would lose all braking power according to his testimony.
That sounds like it.