In a written statement to the Herald on Sunday, North Shore Area Commander Les Paterson confirmed police were investigating Jackman's complaint about the 2010 incident.
Clague went to the High Court at Auckland this week in a bid to stop this paper reporting the police investigation. His lawyer, Mike Lloyd, said the board of Kristin School had told him he would be stood down, pending the outcome of the police investigation, if an article was published.
But Justice Christopher Toogood declined to suppress Clague's identity or injunct publication of this article.
In an affidavit to the court, Clague said the couple had an argument in the driveway of their home where Jackman became "hysterical".
He was concerned that the neighbours and her 8-year-old son might hear.
"I ran over to her and put my hands on her shoulders, imploring her to stop," Clague said.
"I did not do this with any force. It was done more as a pleading gesture. I abhor violence and do not have a violent bone in my body.
"However, as I put my hands on her shoulders, I lost my footing on the garage floor and we both fell.
"Ms Jackman sat down heavily on a small step behind us, bruising her tail bone in the process.
"I apologised to her at the time, helped her up and that was the end of it, I thought. There was no suggestion at the time that what I had done was an assault."
Clague said the allegations had been stressful and caused physical and mental health problems such as chest pains, ulcers and sleepless nights. Worse, they could end his career. "In my profession, in my world, being stood down is literally the kiss of death."
Jackman, a Massey University lecturer of psychology, filed the police complaint against 48-year-old Clague two weeks ago. She alleged the incident occurred at their Greenhithe home in September 2010, two months after their wedding.
The next day, Jackman went to the doctor and said she had fallen down some stairs. She had suffered severe bruising and an x-ray confirmed she had injured her coccyx (tailbone).
She did not mention the confrontation with her husband.
It took her almost two years to leave the acrimonious marriage and a further six months to report the alleged assault to police.
"At first, I didn't leave him because I loved him," Jackman said. "We had just got married and everything was going to be rosy. It takes a lot of courage. I was shaking like a leaf when I went into that police station."
Jackman joined the board of the North Shore Living Without Violence group last year to help others, though she kept her confrontation a secret. "I'm qualified to work as a lawyer, I teach psychology at university, I am on the board of a domestic violence agency and it happened to me," she said.
Philippa Fee, chairwoman of the Kristin board, was told about the allegations earlier this year. After the Herald on Sunday approached her for comment, she convened a board meeting to discuss the school's response.
Clague's lawyer says the board resolved to stand him down if the allegations became public. However, Fee wrote to staff and parents this week expressing the board's "full and unanimous support".
"The Board is taking the matter very seriously and proper processes need to take their course. We wish to assure the Kristin staff, community and the wider public that its priority remains the maintenance of the school's high educational and ethical standards."
Ahead of tomorrow's board meeting, Clague spoke to the Herald on Sunday at his Greenhithe home yesterday. "My career is on the whim of a woman who is angry over a break-up," he said. "Principals don't come back from false allegations like this."
Teachers Council director Peter Lind said the council had not heard from Clague or police. He said the board of trustees was required to inform the council only if a teacher had a criminal conviction which made them liable for imprisonment of at least three months, or if it involved children or staff.
Clague is also president of the Association of Heads of Independent Schools and an executive member of the Independent Schools Association.
