The police have decided not to investigate the Green Party's complaint of alleged criminal activity by Prime Minister John Key's former communications adviser Jason Ede, former Justice Minister Judith Collins and blogger Cameron Slater which was detailed in Nicky Hager's Dirty Politics.
The Greens asked police to investigate Ede's accessing of Labour's membership database in conjunction with Slater in 2011 as well as instances detailed by Hager where Ede and Ms Collins passed information to Slater who used it as fodder for political attacks on Labour on his Whaleoil site.
But police told Greens Co-leader Metiria Turei the database incursion was being dealt with in response to a complaint from Labour.
Police said they had reviewed the other instances of alleged criminal activity
"However each appears to fall short of criminal offending", Detective Inspector Paul Berry told Ms Turei.
Ms Turei said the police had "got it wrong".
"There is clear evidence contained in Dirty Politics that deserves further investigation", she said.
Ms Turei said there was a double standard in the police's stance on the complaint given they were investigating Slater's complaint about the hacking of emails which Hager used as the source material for his book.
"They were quick to take Cameron Slater's complaint seriously and raid Nicky Hager's house, but sat on our complaint for months and still haven't made a decision to look at the clear as day allegations of hacking of the Labour Party database by staff in the Prime Minister's office.
"We would be very concerned if the police are applying different thresholds for launching criminal investigations depending on what side of politics you come from."