Lissie Harper, 30, was left outraged after the trio who caused her husband's death escaped with sentences as low as 13 years – and smirked in the dock
Offenders whose crimes lead to the death of an emergency service worker in the line of duty will receive mandatory life sentences under a new law brought about after the death of a police officer, Andrew Harper.

The ruling, announced by the government, follows a two-year campaign by Lissie Harper, whose husband was killed while answering a late-night burglary call. She previously said she was "outraged" by the sentences handed to the three teenagers responsible for his death.

The new legislation, named Harper's law, will make it on to the statute books through an amendment to the existing police, crime, sentencing and courts bill, and is likely to take effect early next year.

Harper said: "It's been a long journey and a lot of hard work. I know Andrew would be proud to see Harper's law reach this important milestone."

Henry Long, 19, was sentenced to 16 years and Jessie Cole and Albert Bowers, both 18, were jailed for 13 years for the manslaughter of PC Harper, 28. Long, the leader of the group, admitted manslaughter, while his passengers, Cole and Bowers, were convicted of manslaughter after a trial at the Old Bailey. The jury cleared all three of murder.

Harper died from his injuries when he was caught in a strap attached to the back of a car and dragged down a winding country road as the trio fled the scene of a quad bike theft in Sulhamstead, Berkshire, on the night of 15 August 2019.

The sentences prompted Lissie Harper to lobby the government to better protect emergency services workers, a definition that includes police officers, National Crime Agency officers, prison officers, custody officers, firefighters and paramedics.

Announcing the intended law change, the justice secretary, Dominic Raab, said: "We are going to pass into law mandatory life sentences for those who unlawfully kill an emergency worker in the course of their duty. I pay tribute to Lissie Harper's remarkable campaign. This government is on the side of victims and their families and we want our emergency services to know that we'll always have their back."

Priti Patel, the home secretary, said: "PC Andrew Harper's killing was shocking. As well as a committed police officer, he was a husband and a son. It is with thanks to the dedication of Lissie, and his family, that I am proud to be able to honour Andrew's life by introducing Harper's law."

Lissie Harper said that emergency services workers "require extra protection" as they "are put at risk and into the depths of danger" on a regular basis. She hopes Harper's law will provide that protection and said she was "delighted" at the law change.

The courts already have to impose life sentences for murder, although such sentences can also be applied to other violent offences.