Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings. “Management were absolutely complicit in what was going on.”The admissions in the documents are part of their response to the legal case Ms Wilson is pursing through the Investigatory Powers Tribunal, the body that investigates whether police have infringed human rights. There will be a hearing on the 3rd October.It will be the first case heard by the IPT from a woman who had a sexual relationship with an undercover officer who hid his true identity from her.In a statement, Ks Wilson said: “It has taken me eight painful years to discover that managing officers really did conspire to deceive and abuse me, something the police had consistently denied.“The wide questions for society here are massive, this is about institutional sexism, senior police officers sanctioning sexual abuse, and the systematic violation of political beliefs, and we still don’t have the whole truth.”The police force said it would not comment on the revelations because of the ongoing legal action.A spokesperson said: “The Metropolitan Police Service has made clear its position on long-term sexual relationships known to have been entered into by some undercover officers in the past.”Those relationships were wrong and should not have happened.” Police were aware that undercover officer Mark Kennedy was in a relationship with an environmental activist and allowed it to continue, official documents show.In public statements up until recently, police have said they would never sanction such relationships, but legal documents show that they knew Kennedy was in a relationship with Kate Wilson.In the papers lodged with the Investigatory Powers Tribunal, police admit Kennedy’s “sexual relationship with [Wilson] was carried out with the acquiescence of his cover officers and line manager”.Ms Wilson, who is currently involved in legal action against the Metropolitan Police and the National Police Chiefs Council, had a two-year relationship with the undercover officer while he posed as a fellow environmental activist.He used the alias Mark Stone, and unbeknownst to her, he was married with children. She was one of a number of women he had romantic relationships with during his seven years undercover.She began her relationship with him in 2003, but did not find out his true identity until it was revealed by campaigners in 2010, who found that he had spent seven years infiltrating environmental groups.Ms Wilson told the BBC: “The police have said that these cases were a failure of supervision and management, and that is just not the case.