Is there actually a law requiring you to shoulder check before changing lanes or turning? My car has blind spot warning, so I don’t think shoulder checking is necessary anymore. My wife strongly disagrees. She says I should even be checking my side mirrors when I’m going straight, just to be aware of who’s around me. I think that’s my car’s job. Who’s right here? – Kris, Vancouver
There’s no law specifically saying that you have to check over your shoulder – but if you make an unsafe turn or lane change, you’ll have to shoulder the responsibility.
“There’s no offence for failing to make a shoulder check,” said Mike Halskov, spokesman for British Columbia RCMP traffic services. “But you could be involved in a crash – that’s the price you could pay.”
While the rules vary by province, none of them mention looking over your shoulder. But they all say you can’t switch lanes unless you make sure it’s safe.
For instance, B.C.’s law says you can’t make a lane change unless you’ve “ascertained that movement can be made with safety and will in no way affect the travel of another vehicle.”
Rules in most other provinces, including Alberta, Ontario and Quebec have similar language. The same goes for turns: you have to make sure it’s safe before turning.
So, if you switch lanes and cut somebody off – or slam into them – because you didn’t know they were there, you could be charged with making an unsafe lane change.
In B.C., that comes with two demerit points and a $109 fine, Halskov says.
But what if you have blind spot warning (BSW) – a system that uses a camera, sensors or radar to detect cars you can’t see – and it didn’t warn you about the Mack truck in the next lane?
If you fight the ticket or get sued civilly, a judge likely wouldn’t buy “my sensors didn’t work” as an excuse, said Mark Andrews, a traffic consultant and former Ontario Provincial Police (OPP) traffic inspector.
“Who’s in control of the vehicle?” Andrews said. “It’s the driver, not the safety device – I have all the sensors and I still do mirror checks, shoulder checks and blind spot checks.”
Check yourself?
Although laws don’t mention shoulder checks, most provincial driver training manuals do.
In B.C., the manual says, “whenever you plan to change your direction or road position, do a shoulder check to make sure the blind spot on that side is clear.”
That means looking at least 45 degrees over your shoulder, the manual says.
Why do you need to shoulder check? Because most cars have a blind spot where the side and rear-view mirrors can’t show you what’s behind you.
But in many cars, you can reduce your blind spot, or even eliminate it entirely, by making sure your mirrors are adjusted properly.
“You don’t want to see the sides of your car in your mirrors,” said Angelo DiCicco, special projects manager with the Ontario Safety League.
Plus, you should be regularly checking your mirrors regularly while you drive, even if you’re not planning a turn or lane change soon, DiCicco said.
That’s so you know what the other cars around you are doing before they hit your blind spot.
“You should never be passed by a vehicle you have not seen before in your mirrors,” DiCicco said. “If a vehicle disappears, it should be in your blind spot.”
But constantly shifting between your mirrors and the road ahead also helps keep your peripheral vision open, DiCicco said.
“If you’re doing that every two seconds, you actually don’t need to turn your head very far to shoulder check,” DiCicco said. “However, if you’ve been daydreaming or just staring at the vehicle in front of you, then your peripheral vision will decrease and you’ll have to turn your head way farther – like Linda Blair in ‘The Exorcist’”
Blind spot warning useful, but not perfect
BSW – which uses a warning light, a beep or both to let you know that there’s a car beside you – has been shown to reduce lane-change crashes by 14 per cent, said the Insurance Institute for Highway Safety (IIHS).
It’s a useful backup, DiCicco says, but you still need to look to see that it’s clear.
“I’ve had several situations where my blind spot warning let me down,” DiCicco says. “With the weather we’ve had lately, side mirrors can get covered with salt and dirt and windshield wiper fluid and you can’t see the warning light.”
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