Scotland Yard Commander Ali Dizaei said he refused to answer police questions during interview because he thought he was being targeted by the Metropolitan Police over his support for Assistant Commissioner Tarique Ghaffur in his race discrimination claim against Commissioner Sir Ian Blair.
Dizaei, president of the National Black Police Association (NBPA), told the jury at Southwark Crown Court he feared his telephone was being tapped, that he was being followed, and that he was concerned about his personal safety.
He denies assaulting and falsely arresting a young Iraqi businessman who he then left facing prosecution.
Dizaei and Waab al-Baghdadi, 24, rowed over money for a website when they met by chance at the Persian Yas restaurant in Kensington, west London, on July 18, 2008.
Today, Dizaei said officers refused to show him CCTV footage of the incident and a transcript of his 999 call despite repeated requests by his lawyers before the police interview.
He told the court he feared he and others from the NBPA were "being targeted by the Metropolitan Police because of the support we were giving to Assistant Commissioner Tarique Ghaffur because of his race discrimination claim against Sir Ian Blair".
"We feared our telephones were being tapped and feared that we were being followed," he told the court.
Dizaei said he "sought a risk assessment about my personal safety, and the safety of my family and friends in the (National) Black Police Association" in a letter to then Deputy Commissioner Sir Paul Stephenson.
The 47-year-old officer added that he was "nervous" about "the way the allegation was proceeding", with the "drip-feeding" of information in a bid to get him "locked in to one answer".
"This drip-feeding of disclosure, in my view as an experienced police officer, usually leads to miscarriages of justice," he said.
"I don't think it makes sense and I don't think it's right and proper.
"This, in my view, is what you see in the movies."
Asked by Peter Wright QC, prosecuting, if his fears were "nothing more than a smokescreen" to hide discrepancies between his account of events and CCTV footage, Dizaei said: "No, they're not.
"At the time I had no trust or confidence in the investigation. It reinforced my suspicions that there was something not quite right there."
Asked if he had tailored his account to suit the evidence, he went on: "That's not true at all. All I have to say is that accusation is simply not true.
"I haven't tailor-made it or modified it. All I have done is clarified it. I've absolutely no motive.
"I remain a loyal police officer. I love everything about this country for giving me the opportunity to aspire and to achieve my aspirations.
"To suggest that I would throw all that away because Mr al-Baghdadi disrespected me over his website... I'm sorry, but the lines for me just don't join up."
Later, under re-examination by Michael Mansfield QC, defending Dizaei, the officer said: "This was a minuscule part of what was happening in my professional life. It was not on my radar at all."
Dizaei's wife Shy, who was with him outside the restaurant when the incident happened, said she felt "sick" and "very scared" after the confrontation with Mr al-Baghdadi.
Speaking in Farsi and using an interpreter, Mrs Dizaei said: "I was trembling, I was shaking."
She said Mr al-Baghdadi was shouting and swearing as he approached the couple and began to ridicule her husband.
"He was so close, shouting and swearing at me, and at one stage he actually spat on me," she said.
She added he looked "a bit abnormal" at the time and was calm one minute, but shouting the next.
"It was the cause of my fear," she said.
Mrs Dizaei told the jury of six men and six women Mr al-Baghdadi said her husband had to pay for the work on the website or he would "extract the money out of your throat".
She told the court this was an insulting phrase meaning he would resort to any means to extract the money.
She added Mr al-Baghdadi told her husband: "If your wife was not here I would have dealt with you on the spot."
Mrs Dizaei said: "I was pretty scared, my knees were trembling. I was in a state of shock and wanted to get out the car."
Earlier, forensic scientist Nathaniel Cary said allegations that Dizaei's injuries were self-inflicted were based on a "fundamentally flawed approach" to forensic medicine.
"He alleges he has been poked with the shisha pipe," Dr Cary said.
"In my view that's consistent (with the injuries)."
The trial was adjourned to tomorrow.
