Peter Williams QC said the group were taking the action after a settlement offer they made to police got nowhere.
The group, comprising about 30 Tuhoe people ranging in age from under 21 to 77, sent a letter to Police Commissioner Howard Broad on November 9, seeking a restoration of mana and compensation. A positive response was not forthcoming by a deadline of 4pm yesterday.
Police arrested 17 people in raids around the country but the focus was on Ruatoki, 20km south of Whakatane, where police allege terrorist training camps were being run.
Solicitor-General David Collins has since rejected an application to prosecute a number of those arrested under the Terrorism Suppression Act. Charges remain under the Arms Act.
Mr Williams told NZPA none of the group mounting the lawsuit was arrested in the raids.
He said the group's claims would be disclosed at a press conference today in Auckland at midday. Compensation was "part of the package".
Mr Williams expected court documents to be filed in the High Court in about a month's time.
"We are not going to be pushed around," he said.
"We are talking about wrongful imprisonment, we are talking about wrongful arrest, wrongful stopping of cars, wrongful photographing of people," he said.
So far the group comprised members of Tuhoe but "we will embrace all people" abused by the police raids, said Mr Williams.
"This is a community where individuals were abused," he said.
He likened the raids to an invasion, saying up to 400 armed police descended on the community.
"It was unbelievable."Mr Williams said the group had not agreed for the matter to go to Independent Police Conduct Authority