Police chiefs made inquiries about the sex life of a female officer after she threatened to take the force to an employment tribunal, a hearing was told yesterday.

Officers were said to have quizzed colleagues of PC Jean Gauden about a sexual relationship with a senior officer.

Mrs Gauden, a mother-of-two, told the tribunal, in Newcastle, that colleagues were also asked whether they had sex with her.

She is seeking compensation from Northumbria Police, claiming she was denied promotion throughout her career because she is a woman.

The tribunal saw a note from one of the officers looking into Mrs Gauden's claims. It only had one line about her ability to do the job, with the rest of the page taken up with allegations about her sex life.

Despite passing her exams and being qualified to inspector level, she did not progress beyond the rank of constable in 28 years.

Mrs Gauden said the force inquired about her sex life to embarrass and humiliate her.

She said a document prepared by the force hinted she was offered a transfer to another department headed by ex-detective chief superintendent George Hale, with whom she was alleged to have had a sexual relationship.

Investigating officer Inspector Diane Winship admitted she had asked Superintendent Neil Lynch whether he was aware of a relationship beween Mrs Gauden and her former supervising officer.

Mrs Gauden said: "I had colleagues telephoning me out of the blue to say they had been asked if they had sex with me."

Det Insp Winship admitted officers were questioned about Mrs Gauden's sex life and an alleged relationship between Mrs Gauden and Mr Hale.

She said that, after taking lawyers' advice, the force had decided to question witnesses as part of an investigation into allegations Mrs Gauden had suffered discrimination after her divorce from Superintendent Peter Gauden.

Mrs Gauden, 49, of Kenton Bank Foot, Newcastle, claims she was taunted over the success of her former husband.

Det Insp Winship said: "The investigation team asked a selected number of witnesses. It was a small part of a very large investigation."

But she said the force had not set out to humiliate and embarrass Mrs Gauden, nor had her colleagues been asked if they had sex with her.

The case continues.