Mr Harries' life now lies in tatters. He has contemplated suicide; he has received psychiatric counselling; he is still taking anti-depressants for the nervous breakdown prompted, he says, by Geoffrey Owen's inspection.
Mr Owen was only struck off the list of registered inspectors last week after the latest in a string of complaints against his "predatory" techniques.
Mr Harries, 47, a father of two, is unable to work again. His doctor diagnosed reactive depression and post-traumatic stress disorder. He was forced to take early retirement due to ill health from his job as headteacher of Hillbrook primary school, in Tooting, south London.
"I found myself celebrating when Mr Owen went down but at the same time I think this guy is as much a victim of the system as me. Ofsted encouraged a witchhunt mentality. His mistake was to get over-enthusiastic about it.
"It seems to me the whole episode is not so much the story of a chap completely off the rails so much the story of an organisation which has made that kind of thing possible and even likely."
The beginning of the end can be charted to the day in September 1995 when Mr Owen walked into the school to start a five-day inspection.
"To begin with Mr Owen appeared efficient and polite so I didn't anticipate any problems. By the end of the Wednesday, I knew I had a predator on the premises and there was nothing I could do about it," John Harries recalls.
Teachers, including the deputy head, had been upset by Mr Owen, who famously told Mr Harries on the fourth day that the Ofsted team was "the Rolls- Royce of inspections but this was of course little consolation to those who might be crushed beneath the wheels".
"It was a staggering remark," said Mr Harries. "But the notion he might fail the school didn't enter my mind.
"The following day he spoke to me in my office at the final briefing. The words 'special measures' were trotted out and I went into shock. By the end of the briefing I couldn't speak." Suffering from stress, Mr Harries was off sick for the next five weeks.
In February 1996, he complained to the chief inspector of schools, Chris Woodhead, along with three other heads whose schools had also suffered at Mr Owen's hands. Ofsted, says Mr Harries, promised an independent investigation.
"But Ofsted didn't contact me or any of the other heads. And they expect us to believe that was independent and impartial."
By April 1996, with the school in chaos, his health finally collapsed and Mr Harries had a breakdown. "My feeling is if Ofsted had acted as promptly and responsibly as they did to the latest complaint from Bristol, it would have given me sufficient boost to recover and remain in the job I loved. It was very much my life.
"The thing you felt so proud of is suddenly a source of shame and there is nothing worse than that. For a long time I couldn't cope at all. I couldn't even mow the lawn."