Clifford was jailed for eight years in May 2014 after being convicted of a number of charges under Operation Yewtree, the Met Police investigation set up after the Jimmy Savile scandal.
Giving evidence on the first day of his defence for allegedly indecently assaulting a 17-year-old girl more than three decades ago, Clifford said he hired private investigators to help prove his innocence in this case and the previous trial two years ago — allegations he said “disgusted” him.
The 73-year-old said: “I was found guilty... I know I’m innocent. Hopefully one day I will be able to prove that.
“I know I was not guilty. One of the things I have learned [from the last trial] is you’re guilty until you’re proven innocent when sexual offences are involved.
“I have had the money to be able to employ private investigators for this trial. They are all ex-Met Police. They know the way police think and what they get up to.”
Asked what he had tasked the private investigators with, Clifford replied simply: “To tell the truth.”
The alleged victim in the latest trial claimed she was assaulted by Clifford at his Mayfair offices in New Bond Street between October 1981 and May 1982.
He allegedly locked the girl in his office and forced her to engage in a sexual act with him, the trial at Southwark Crown Court heard.
Clifford told the jury he was not always faithful to his late wife of four decades, Liz, but insisted he loved her.
The trial continues.