A retired Metropolitan police detective has accused both Priti Patel and Cressida Dick of ignoring evidence of “vulgar and sexist” WhatsApp group messages involving police contractors and police officers.

Former Det Supt Paige Kimberley said she wrote to the home secretary and the head of the Met shortly after the murder of Sarah Everard asking for a review of “how inappropriate behaviour is addressed amongst contract workers”.

The Independent Office for Police Conduct is now investigating “offensive and abusive” sexist messages shared by a WhatsApp group that involved Everard’s murderer, Wayne Couzens, which was a different group from the one Kimberley was in.

Kimberley is set to be compensated after a tribunal last month ruled a job offer was withdrawn from her a day after she told her civilian line manager about sexist messages and images on the WhatsApp group.

An internal investigation in 2019 took no action against the male officers, saying the messages were “distasteful” but did not amount to criminality or misconduct.

Kimberley said she wrote to Cressida Dick in March this year about the “vulgar and sexist comments that were circulating on the WhatsApp group that one of the contractors (an ex senior officer) has put in place”.

According to Mail Online, Kimberley said: “I sent it recorded delivery. I never got a reply. I also wrote to the home secretary, Priti Patel, but did not get a response. It has cost them an awful lot of money to defend this case and they tried to discredit me,” she said.

Kimberley was commended seven times during her 32-year career with the Met. An employment tribunal in London heard she retired in 2013 but four years later she was approached to rejoin the Met as part of its digital policing strategy.

She was offered the role as one of its implementation managers and the team consisted of retired male senior officers, a serving constable and a civilian IT specialist.

Kimberley said a WhatsApp group was created by the team members so “we could keep in touch and assist each other with any problems that arose”, she said – adding that the name of the group was “Old Timers plus Dave”.

She said as time went on posts in the group evolved into light-hearted conversations between colleagues.

After Kimberley left the role she remained on the WhatsApp group. “As soon as I left, I noticed that the language and images being shared within the group began to become graphic, sexual and derogatory towards women,” she told the tribunal.

She claims her male colleagues were aware she was still in the group but “they continued to publish statements, images and videos which were negative towards or about women” – up to 20 messages a day.

In her statement to the tribunal, Kimberley said: “I was shocked and disappointed by the content of these messages.

“Yet despite their respective responsibilities, and on whose behalf they were working, and being paid reasonably high amounts by the taxpayer, they were still circulating aggressive and inappropriate messages, photographs and videos in a work WhatsApp group, including a graphic image of a diseased vagina, messages calling women slags and disclosing very misogynistic and sexist attitudes towards women.”

Kimberley told the tribunal that when she was asked to return in September 2019 she did not feel she could until the content of the WhatsApp group had been addressed, and claimed the conduct by the contractors had created a “hostile and offensive environment to me”.

A Met spokesman said: “We are currently assessing the details of the tribunal’s finding. We cannot comment further at this time.”