Dangerous drivers who cause death while using their mobile phones or speeding will face life in prison, ministers have confirmed. The decision to go ahead with a major extension of sentences comes after a campaign by families and a cross-party group of MPs.

Drivers who kill while under the influence of drink or drugs will also face a life sentence. And there will be a new offence of causing serious injury through careless driving, as part of renewed efforts to improve road safety.

The new measures mean such drivers could face the same length of sentence as those convicted of manslaughter, with maximum penalties raised from 14 years to life.

Last year 157 people were sentenced for causing death by dangerous driving, with a further 32 convicted of causing death by careless driving while under the influence of alcohol or drugs.

Tory MP Heidi Allen has been campaigning for life sentences for death by dangerous driving. The South Cambridgeshire MP has been supporting the family of a 21-year-old who was killed after being hit by a car on a night out. The killer was sentenced to four years, but was released after two. Labour’s Judith Cummins also pressed the government on the issue in July.

Dominic Raab, the justice minister, said: “We’ve taken a long hard look at driving sentences, and we received 9,000 submissions to our consultation. Based on the seriousness of the worst cases, the anguish of the victims’ families, and maximum penalties for other serious offences such as manslaughter, we intend to introduce life sentences of imprisonment for those who wreck lives by driving dangerously, drunk or high on drugs. We will introduce a new offence of causing serious injury by careless driving, punishable by imprisonment, to fill a gap in the law andreflect the seriousness of some of the injuries suffered by victims in this category of case.”In response to a government consultation on dangerous driving, 70% of responses backed extending the maximum penalty for the offence to life imprisonment.