Mary Archer's sacked assistant, explicit e-mails and torrid days at the Old Vicarage

Lady Archer and her former personal assistant heaped insults on each other yesterday at an employment tribunal. The wife of the jailed Tory peer was accused of being spiteful and rude, of giving insultingpresents to her staff and behaving in a bizarre manner.

Lady Archer said her assistant, Jane Williams, had received explicit sexual e-mails and sent offensive, indiscreet correspondence about her from the office computer. The PA had tried to force her employer into a pay rise in return for her continuing discretion, it was claimed.

The rowsat the Old Vicar-age in Grantchester, near Cambridge,were laid bare as Ms Williams brought a case for unfair dismissal.

Lady Archer, 57, in tailored blue suit and pearl earrings, appeared composed at the tribunal hearing in Bury St Edmunds. She said she had warned Ms Williams, 49, about receiving "pornographic and indecent'' e-mails after opening some of her correspondence, adding: "I found it disturbing to find my PA was e-mailing rude stuff about me to her friends."

The wife of the millionaire author, who is serving four years for perjury at an open prison in Boston, Lincolnshire, said she had been upset to discover that a woman on whose loyalty she relied had been sending "disparaging e-mails''.

Ms Williams of Saffron Walden, Essex, was sacked by Lady Archer, a professor in solar energy, in June last year after 13 years handling her personal affairs.

Five years earlier she had been runner-up in the PA of the Year competition, and described as skilled and dedicated by her employer. But Lady Archer insisted yesterday that her performance and her manner had deteriorated. "She was sullen and sometimes rude. She would slam doors and she would down tools at five o' clock even if there was something quite urgent," she said.

But it was the e-mails ­ downloaded by the peer's wife after a flood in the "folly'' they used as an office caused technical problems ­ which were the substantive issue of the matter. The cursor may have fallen on and opened some of them, she explained.

"I felt the e-mails were inappropriate. Some of them were really rather childish. It was rather unprofessional to be sending e-mails with that tone. One or two of them were being indiscreet and gossiping about me,'' Lady Archer said.

"There are strict laws about pornography and indecency. It seemed to me they crossed the borderline of what could legally be sent and what could not."

Lady Archer said she was generous with salary rises, adding: "Jane's refrain that she was underpaid was a rather constant one and I have to say I didn't agree with it."

In January 2001, Ms Williams wrote to Lady Archer complaining that her husband's PA was better paid. "It seemed to me that a couple of her remarks which suggested I should be uplifting her salary to buy her confidentiality were highly inappropriate," she said.

Ms Williams said Lady Archer could be rude, spiteful and dislikeable. "She acted in a bizarre manner when it came to birthdays and Christmases. She gave me what amounted to insulting and embarrassing gifts." One year she received an open bottle of flat champagne. On another she was given a "Calvin Klein" watch bearing a Made in China sticker.

Ms Williams said that when Lady Archer offered to replace diamonds which had fallen out of a ring she had returned it unrepaired but wrapped as a gift.

Lady Archer said no diamonds had been replaced because the jeweller said the ring had never contained any. The hearing continues.