Adelaide drivers don't have the best reputation when it comes to… well, driving.

Even locals are willing to admit that skills like patience and vigilance are sometimes in short supply on South Australia's roads.

"South Australia is right up there with the worst, particularly when it comes to being impatient [and] lacking in courtesy," SA Police's then commissioner Gary Burns told ABC Radio Adelaide in 2015.

But how much truth is there in the claim that Adelaideans are not just bad drivers, but the most abysmal in the nation?

That's the question put to us by one Curious Adelaide reader, so we decided to take a look at the evidence.

What is a bad driver?

We went straight to the source: SA Police.

SAPOL told me that in its view "bad" was not necessarily a measurable quality.

"Of overarching importance to police is reducing fatal and serious injury crashes, and the factors that lead to those — often referred to as the fatal five; Distraction, Speeding, Dangerous road users, Seatbelts and Drink/drug driving," a spokeswoman said.

SA's Royal Automobile Association (RAA) offers a broader definition.

It lists a lack of knowledge of road rules, a lack of patience, being unable to deal with changing conditions, a sense of entitlement and a lack of common courtesy.

A car with a metal pan for a steering wheel was spotted in Adelaide's CBD in 2016. ( Supplied: SAPOL )

And there are plenty of dash camera videos exposing all sorts of dodgy driving behaviour in Adelaide; from running red lights or cutting others off, to the downright dangerous and utterly silly.

The fact that there are no less than three pages on Facebook dedicated to bad South Australian drivers suggests there might be substance to the widely held suspicion.

"I think Adelaide has a belligerence about itself with driving that I have never seen anywhere else," driving safety expert Tony Hastings told Curious Adelaide.

Tony Hastings says Adelaide drivers are the most belligerent he has seen. ( ABC News: Malcolm Sutton )

"In Sydney and Melbourne the density of traffic dictates that you must cooperate.

"The lanes are not the width of the lanes we are used to in South Australia and yet collisions between vehicles in that close proximity are really quite rare."

So, what do the statistics say?

Nationally, the number of people killed in car crashes each year tends to be around five per 100,000 people.

South Australia recorded exactly 5.0 road fatalities per 100,000 population in 2016 — slightly below the national average of 5.4.

The worst state or territory was the Northern Territory with 18.4.

The more populous states of New South Wales, Victoria and Queensland recorded 5.0, 4.8 and 5.2 fatalities per 100,000 population respectively, while Western Australia, Tasmania and the ACT had 7.4, 7.1 and 2.3.

But the RAA's senior manager of road safety, Charles Mountain, urged caution when interpreting the data.

"In some instances, it's simply a case of a momentary mistake that leads to a fatal outcome," he said.

A stolen car that plummeted from an overpass onto the Southern Expressway in February 2015. ( Facebook: Adelaide Police Locations )

Motor Accident Commission (MAC) research found attitudes to speeding have improved in South Australia over the previous decade.

MAC found a significant increase in the number of motorists who stick to the speed limit from one in five in 2008 to more than three in five in 2017.

But more than 242,000 traffic expiations were issued in 2016-17 alone from speed cameras — which is a lot, given that there are just over 1.2 million licence holders in South Australia.

More than 5,000 drivers were caught drink driving with an illegal blood alcohol concentration in South Australia in 2016.

According to MAC's data, 37 per cent of drivers or motorcycle riders who were killed in crashes from 2012 to 2016 were on drugs or had been drinking, or both.

Methamphetamine, or ice, has quickly become the most commonly detected drug in South Australian motorists, 2,903 of whom tested positive to ice in 2016 compared to 533 in 2010.

What do insurers say?

A 2013 study conducted by financial website Canstar found South Australians were the most crash-prone drivers in the nation, with eight insurance claims per 1,000 registered vehicles.

Victoria and New South Wales had just below eight claims per 1,000 vehicles, while the ACT had the fewest claims at just 0.37 per 1,000 vehicles.

Given we tend to think of merging lanes as one of the worst skills on show in South Australia, I asked the Insurance Australia Group (IAG) about that.

IAG calculated that while merging collisions were one of the more typical claims it received, South Australians only made 110 claims for that type of crash in 2017, compared with 450 in New South Wales.

But given that New South Wales has a population roughly seven times that of South Australia, the figures don't bode all that well for SA.

How bad is SA's road rage?

When it comes to road rage, Adelaide drivers were recently rated the second worst (behind Canberrans) in the country in a survey by insurance provider AAMI.

More than 83 per cent of respondents in Adelaide said they had experienced road rage, noticeably higher than the national average of about 75 per cent.

Another survey of RAA members in South Australia found more than 85 per cent of respondents had copped abuse from other road users, including obscene gestures, aggressive honking, tailgating and verbal insults.

Almost 60 per cent were even willing to admit they had directed the same kind of behaviour towards others.

"South Australian drivers have some of the strangest habits I've seen anywhere in the world," said Tony Hastings, who chairs the defensive driving organisation Drive to Live.

This truck with vice grips on its brakes was stopped and seized on the South Eastern Freeway. ( Supplied: SA Police )

He pointed to the fact that many seem unwilling to let drivers cut in when the roads are congested, but will instead "accelerate to close the gap you are trying to get into".

"We are also prolific at ignoring road rules and the most obvious of those would be the 'keep left unless overtaking' rule."

Despite passing their driving tests, many motorists actually do not seem to understand the road rules.

"Each time we conduct a slip lane versus zip lane survey on our social media accounts, it's clear many motorists still don't understand when to apply each rule," the RAA's Charles Mountain said.

He added that many people continue to believe, wrongly, that the default speed limits "are 60 kilometres per hour in built up areas and 110 kilometres an hour on rural roads".

Charles Mountain is concerned many drivers don't know the road rules. ( ABC News: Malcolm Sutton )

"Yet these were reduced to 50 kilometres per hour and 100 kilometres per hour respectively in 2003."

What's the reason?

Mr Hastings has a theory about why Adelaideans have such a reputation: and it's to do with the size of the city.

"Somewhere like London, given its density, you'd think that [Adelaide] would be a much easier place to commute, but London is one of the most courteous places I have driven in the world," he said.

"In a lot of Asian cities, the traffic sorts itself out without having rigid rules about which lane they must be in, how they're allowed to merge.

"They do some of what appears to us to be the most bizarre things but it all works because they have the freedom of choice."

An Adelaide man was caught riding an unregistered and uninsured motorised Esky in 2015. ( SA Police )

Adelaide drivers, he suggested, are especially sensitive and intolerant because their expectations are too high.

"In Adelaide it appears the moment you do something wrong you … incur the wrath of every other driver around you."

But what does Mr Hastings consider a "good driver"?

"A good driver blends in with the traffic and reads the traffic," he said.

"The aggressive driver will stand out by tailgating or erratic lane changing or even trying to teach others to read lips."

The final word

Many of us have our own stories about poor driving, because we love complaining about how bad other motorists are.

This car using vice grips instead of a steering wheel was pulled over in 2013. ( SA Police )

But just as you prepare to steer clear of South Australians on the roads, or write off Adelaide's motorists, pump the brakes and consider this final piece of data.

In 2015, an Australian car insurer surveyed more than 1,000 drivers asking them: which state has the worst drivers?

It turns out that most drivers, regardless of where they come from, think their own state or territory has the worst drivers.

So, food for thought, especially if you're reading this on your commute.