Insurance giants Direct Line, Aviva and Zurich reveal motorists face higher insurance premiums

The Scottish Government proposals also risk road safety by removing a strong deterrent to drive responsibly, the insurance industry and charities warned, leading to calls for ministers to perform a U-turn.

Under the proposals, those who receive fines, including for endorsable driving offences such as speeding or driving without insurance, would see them become 'spent' after just 12 months, rather than five years currently.

The changes could also affect drink-drivers, who could also see their convictions become spent, meaning they would not have to be declared after just a year depending on their sentence.

Insurers said depriving them of a key tool in assessing how likely a potential customer is to have an accident would mean across-the-board price increases that would hit careful motorists.

In a response to a Scottish Government consultation, the Direct Line Group said that plan was "extremely disproportionate" and would leave it unable to identify drivers whose behaviour had put lives at risk.

It added: "If insurers are only able to ask for endorsable motoring offences which are less than 12 months old, insurers would no longer have the ability to identify those drivers who drive without care for motoring laws, such as speed restrictions.

"The impact of this would be to share the risk across all the drivers resident in Scotland, thus increasing the premiums for those drivers who have not committed any motoring offences.

"The Scottish Government proposals would lead to a significant dumbing down of serious offences, which would normally lead to a higher insurance premium, and would remove one of the deterrents against poor driving behaviour - people generally drive more responsibly after motoring convictions until the convictions are spent."

Insurers also expressed fears that if brought in, the law changes may create confusion as Scotland would have a less strict regime that England and Wales, where driving offences remain unspent for five years, and that some firms may pull out of the country altogether.

Among other companies to express concerns were Aviva, which warned of the impact on "honest customers", and Zurich Insurance, which said increases to costs for drivers without convictions would be inevitable.

In its submission, the Forum of Scottish Claims Managers said: "Reducing the period to one year would have a damaging and negative impact on road safety and lead to higher motor premiums for safer drivers."

Gary Rae, campaigns director for road safety charity Brake, said the proposals could essentially "air brush out" driving convictions after 12 months. He added: "We’re seriously concerned that this could remove any obligation for some drivers to drive safely, as well as potentially increasing insurance premiums for all drivers."

Opposition MSPs called for a U-turn in light of the criticism. Alex Johnstone, the Conservative transport spokesman, said it was "quite extraordinary and unfair" that law abiding drivers would see their insurance premiums rise.

He added: "Once again, the SNP government have obviously not thought through the wider implications for all drivers. How is it fair that good drivers will be hit hard in this way? Road safety may also be badly hit, with there being less of an incentive to drive carefully. The nationalists need to rethink these imprudent plans."

The changes were proposed as part of a widespread overhaul to the Rehabilitation of Offenders Act, after ministers accepted that the law did not achieve the right balance between protecting the public and allowing offenders to put mistakes behind them. Employment opportunities can be severely restricted if offences must be declared.

Other proposals include ensuring only convictions resulting in a prison sentence of at least four years, compared to 30 months currently, would never become spent. Community Payback Orders are among non-custodial sentences that would become spent after one year plus the length of the order, compared to a blanket five years currently.

A Scottish Government spokeswoman said an independent analysis of the consultation responses would be published by December. She added: "The responses received to the consultation will inform Scottish Government decisions about next steps in this area. This includes in the area of road traffic offences.

"Protection of the public will remain at the forefront of any future decisions, which will be made after the analysis has been completed and scrutinised."