//In April 2013 the law relating to the disclosure of criminal convictions changed, meaning that your insurance company has to ask the necessary questions to work out if they can provide insurance for you.
If you’re not asked directly but you think you have a conviction that should be declared, it would be best practice to read the terms and conditions and/or speak to your insurer about it.
Following the April 2013 law change, convictions considered spent under the Rehabilitation of Offenders Act 1974 no longer need to be disclosed.Car
This means that such convictions can effectively be ignored after a certain amount of time, making it easier for people with a conviction to buy car insurance.
However, this change in law doesn't apply to persons whose conviction resulted in a prison sentence of more than four years. //
http://www.gocompare.com/car-insurance/cover-for-drivers-with-a-criminal-conviction/