Carol Hawkins, who began working for Clayton in 1992, has been charged with 181 counts of stealing checks from him.
Dublin’s Circuit Criminal Court has heard that Hawkins worked for a salary of up to £38,700 (about $60,000) per year and that she lived rent-free in his Georgian mansion in Rathfarnham, in the south of the city.
“I trusted people, and that’s why we’re here today,” BBC News quoted Clayton telling the court.
Prosecutor Colm O’Briain told the court how the U2 bassist made Hawkins a signatory to a number of his bank accounts, and that between 2004 and 2008 she had withdrawn euro 2.8 million from them.
Hawkins is alleged to have deposited the money in three accounts of her own, which were her personal account, a joint account with her former husband John Hawkins, who also worked for Clayton as a driver, and a Bank of Ireland Credit Card Services account.
Things seemed to turn for the worse around 2007 when Hawkins began having marital trouble.
“She also mentioned that she had been suicidal and had taken an overdose," Clayton reportedly said in court. “I was concerned for her health and recommended she see a therapist. I got her a therapist locally.
“In the matter of the money, I accepted she was a distressed woman. Her marriage broke up, her children had gone away.
“I said we would have to verify the amounts she had been claiming.”
Clayton said he removed Hawkins as a signatory on his accounts, but kept her as an employee.
“I felt she looked after my money and on many occasions accused others of being greedy so I was extremely surprised,” BBC News reported Clayton saying.
On June 20, U2 financial controller Gaby Smith said that in 2008 Hawkins oversaw the euro 50 million refurbishment of Clayton’s mansion in Rathfarnham, which included approving payments for the work.
The trial is expected to last for another month.