Image caption Essex Police disputes PC Chapman's allegations

A transsexual police officer is suing her force after she allegedly had to "out" herself over a police radio system, the BBC has learned.

PC Emma Chapman claims Essex Police failed to help its officers understand transgender issues and properly investigate what had happened.

The case, believed to be the first of its kind, was heard at an employment tribunal which is now considering its findings.

Essex Police disputes the allegations.

PC Chapman, 44, was born male and underwent gender reassignment in 1999 while serving as a volunteer officer with Essex Police.

'Lack of understanding'

Four years later she became a full-time constable and now works on the force's response team. It is thought she is the only transgender officer in the force.

PC Chapman said that after initially telling people about the sex change and raising awareness of transgender issues at conferences, she became "frustrated" at the lack of support and understanding about the problems transsexuals faced.

She decided not to be "open" any longer and "stepped away" from dealing with transgender issues in 2009.

According to legal documents, seen by the BBC, her claim centres on three incidents when she had to speak to the police force's control room via her radio handset.

PC Chapman says that on the first occasion, in October 2012, the operator did not believe who she was, saying she had a "male voice".

In her witness statement, the police constable said: "I felt a combination of alarm and distress.

" I replied... 'I am a transsexual'.

"I felt very embarrassed and desperate. The incident took my breath away."

PC Chapman said she was left feeling "very distressed" that she'd had to "out" herself over a radio channel that was listened to by hundreds of officers and staff.

She reported what had happened but claims Essex police failed to carry out a full investigation and interview the control room operator.

The radio is also a lifeline at times and I should not have to feel hesitant or anxious about using it. PC Emma Chapman

Legal papers say two further incidents occurred in June 2013 when the officer was again challenged by control room staff who questioned her identity.

"I felt a growing sense of apprehension whenever I had to use the radio, concerned that there may be further, similar incidents," she said.

"The radio is also a lifeline at times and I should not have to feel hesitant or anxious about using it."

PC Chapman, who's a Police Federation constables representative in Essex, secured the backing of the federation to bring legal proceedings against the force.

Decision in months

The officer said the incidents created an "intimidating, hostile, degrading, humiliating or offensive environment" for her to work in.

She is seeking compensation for injury to her feelings and a declaration of discrimination and wants the force to improve the way it deals with transgender issues.

Essex Police said it "disagreed" with PC Chapman's assertions and was contesting the case.

A spokesman acknowledged that conversations between PC Chapman and the control room had taken place but said the force disputed the "precise wording and tone" said to have been used.

The case was heard at the East London Tribunal Court last week after PC Chapman turned down an out-of-court settlement.

A decision is expected in the next few months.

It is thought that, if she is is successful, PC Chapman could receive compensation of up to £3,000, though her main objective is said to be to highlight the way transgender people are treated.

Roy Scanes, Essex Police Federation's branch board secretary, confirmed that PC Chapman had the federation's backing for what was an "important" and "unusual" case but declined to comment until there had been a ruling.