Legg drove off, stopped near a house and ran off.
Relieving district commander Detective Inspector Karyn Malthus said a police dog and handler tracked Legg some distance.
He was arrested and handcuffed and taken back to his car which involved climbing a wire fence.
Malthus said Legg fell and received a significant neck injury while climbing the fence. He was taken to Whangarei Hospital where he remained in the Intensive Care Unit.
Ray Legg earlier said his son had limited arm and leg movement and was having surgery after doctors told the family the young man's vertebrae had compounded over each other and trapped the spinal cord.
Shane Legg was yet to be spoken to by police about the incident, although there were officers at hospital as he remained in police custody.
A number of witnesses and the police officers involved were being interviewed.
Malthus said there were conflicting accounts between Legg and some of the civilian witnesses already interviewed by police.
The officers involved in the arrest had not been suspended.
To donate towards Shane's family and hospital treatment you can give money to the following account. 38-9002-0100866-00 S F LEGG KIWI BANK WHANGAREI
