The safety of women travelling alone at night has become an urgent political issue following the brutal murder of Sarah Everard, a 33-year-old marketing executive who was snatched at random off the streets in south London, bundled into a hired car, raped and strangled before her charred body was dumped in a builder’s rubble bag in Kent.

On Friday, a 48-year-old man, Wayne Couzens, pleaded guilty to her murder at the Central Criminal Court in London. On June 8, he had pleaded guilty to Sarah’s kidnap and rape on March 3, 2021, and also admitted responsibility for her death.

What makes Sarah’s murder particularly horrifying is that Couzens is a senior, armed police officer, a member of Scotland Yard’s elite Parliamentary and Diplomatic Protection Command, whose job was to protect the US embassy as well as the royal family.

Jim Sturman QC, defending, said: “His pleas today represents a truly guilty plea and remorse for what he did and, as he put it to us this morning, he will bear the burden for the rest of his life — his words: ‘as I deserve’.” He will be sentenced on September 29, with the judge, Lord Justice Fulford, warning he was considering a whole life tariff —meaning Couzens will never be released from prison.

Outwardly, Couzens, who has a son and a daughter, aged 11 and nine, with his Ukrainian-born wife, Elena, appeared to be a devoted family man but there was a hidden darker side to his character.

He was vetted before he joined the police and also when he transferred to the Metropolitan Police but on at least two occasions, disturbing aspects in his character were not detected.

In Dover in 2015, he was spotted driving naked from the waist down. On February 28, 2021 — just three days before he kidnapped Sarah — he twice exposed himself indecently at a McDonald’s drive-through restaurant in London. He was questioned by police but no further action was taken.

The head of Scotland Yard, Cressida Dick, who has been asked to resign because of this and other alleged failures in her leadership, acknowledged: “All of us in the Met are sickened, angered and devastated by this man’s truly dreadful crimes. Everyone in policing feels betrayed.”

During the pandemic, people were being urged to walk whenever possible instead of taking public transport.

Sarah was walking home at 9pm after sharing a bottle of wine with a friend in Clapham in south London. She made a 14-minute call to her boyfriend, Josh Lowth, who raised the alarm the following day when Sarah failed to keep the appointment they had made.

Scotland Yard police officer Wayne Coutzens

As she set out for the 50-minute journey for her flat in Brixton 2.5 miles away, Sarah was spotted alone on CCTV cameras at 9.15pm and 9.28pm, from a marked police car at 9.32pm and then from a bus at 9.35pm. But the bus camera picked up a Vauxhall Astra with its hazard lights flashing. Footage from another bus detected the same car. Its number plate was read and it was this hire car that led the trail back to Couzens and his eventual arrest.

Somewhere in Kent he transferred Sarah to his own car where the rape and murder are believed to have taken place. He didn’t know Sarah but had previously bought “a roll of self-adhesive film advertised as a carpet protector, two green rubble bags, a 2m by 2m tarpaulin and a bungee cargo net”.

Many campaign groups are now pressing the government to take urgent action to make the streets safer for women.

On Saturday, Jess Leigh, from Our Streets Now, told the BBC Radio 4’s Today programme: “It kind of really pains me to say that nothing much has changed really in the sense of law and legal battles. Public attitudes are changed in the sense that now more men know that these crimes take place. But it should never have taken a woman to die for anything to change.

“We want to see a bill introduced to criminalise public sexual harassment. Street harassment is quite shocking in this country. You can get fined for dropping a cigarette. But you can shout horrific, awful things at girls and women and there’d be absolutely no repercussions.”

Baroness Gabby Bertin, a former adviser to David Cameron when he was Prime Minister – her 18-year-old cousin was killed by the “local sex pest” – told the same programme: “What we’ve got to remember is that you don’t generally wake up and become a murderer, you don’t generally wake up and become a rapist, you work up to these things. Jess’s point is right that “low grade crimes” are not necessarily low grade crimes at all. And harassment in the street should also be taken very seriously.”