A sheriff is being sued by his former secretary after she was sacked for calling him and his wife "nutters" in an email. Sheriff David Clapham discovered Susan Nelson made the comment in an email to her sister last September. Clapham, who sits as a part-time sheriff and is also an immigration judge, fired Mrs Nelson from his law firm as he found the remark "hurtful". Mrs Nelson has now lodged a claim of unfair dismissal against Clapham Solicitors at an employment tribunal. The hearing was told how she started working at the lawyers in Clarkston, near Glasgow, in June 2009. But Mrs Nelson clashed with Clapham's lawyer wife Debra last year after returning from holiday. She alleged Mrs Clapham - a joint partner in the firm with her husband - "bawled" at her. Mrs Nelson decided to resign after the row but changed her mind and was allowed to stay. But before her re-think, she had written an email to her sister referring to the couple as "nutters, the two of them". The email also stated that she had spoken to people at a fitness class, saying: "Told everyone what happened, they were all appalled." The email continued: "Telling everyone in Clarkston that I meet, all disgusted". Clapham - who has presided in sheriff courts at Greenock, Perth and Airdrie - found the email last September after it got mixed up in his papers. He and his wife confronted Mrs Nelson, who claimed it had been written in a "fit of rage". She was eventually sacked as the couple felt she had "maligned" the firm. Mrs Clapham told the tribunal that their former employee had not given "any satisfactory explanation" for what she said. She added: "I didn't trust her. What was going through my mind was, 'What else has she done?'." Mrs Nelson, of Clarkston, admitted at the hearing that she "regretted" what had happened. She added: "It is not generally like me to do something like that. I think I was just so upset and I felt totally stressed out." The tribunal panel, led by employment judge Roderick MacKenzie, will make a written judgment later this year.