The council said accidents were not a “primary factor” in their studies – and that they did not have statistics for levels of traffic, cyclists and pedestrian use.
Opponents today slammed the council’s “blanket approach” and insisted the failure to prioritise crash rates was a “serious omission”.
Around 80 per cent of the Capital’s roads are set to be slapped with 20mph limits under plans given the go-ahead by council officials on Tuesday.
And yesterday city chiefs claimed their formula of targeting main urban streets naturally included many roads with high accident rates.
But Neil Greig, director of policy and research at the Institute of Advanced Motorists, insisted the council risked provoking complaints.
He said: “When Lesley Hinds and the council talk about 20mph limits, they always talk about road safety, so you would expect that one of their key criteria and one of their key measures of success would have to be accidents.
“I’m surprised they have not taken accident rates into account. It seems to be quite a serious omission.
“They should have taken crash history into account, but the problem was they were going for this blanket approach.
“And when you start to have this blanket approach, you are going to have 20mph limits on streets that are perfectly safe to drive at 28mph or 27mph.”
Under the plans, all city centre roads are to be covered by the 20mph limit, as well as streets with at least 400 metres of shops and businesses. Roads with tenements and other high-density housing will also be covered.
But Mr Greig insisted the proposals would have been better implemented on a “street by street” basis.
He added: “There’s a lot of support out there for the plans, and we understand that – but if you start putting the limit on roads that don’t have a problem then you perhaps risk the unpopularity of the policy.
“If they are going to sell 20mph as road safety, they need to back it up with road safety figures.”
And Raymond Davidson, former secretary of Edinburgh Taxi Association and a taxi driver in the city for more than 40 years, condemned the council’s approach as “confusing.”
He said: “It’s going to be gridlock – things are bad enough in the city centre.”
A council spokeswoman said: “Numbers of casualties were not a primary factor in determining which streets to propose for 20mph.
“This is because there are some roads with higher numbers of casualties, for example Telford Road, where a 20mph limit is not practicable given the nature of the road itself.
“However, maps of pedestrian and cyclist casualties reveal the extent to which these are concentrated on main urban streets that would have a 20mph limit under the current proposals.”