Groenewald, a South African who took the job in May last year, said his resignation is “indirectly” related to a case of alleged police brutality.
A video emerged online three years ago apparently showing Fijian officials beating several prison escapees with wooden and metal poles.
An investigation into the beating has been completed and the case referred to public prosecutors, according to local media.
Last week, the Fiji military announced it had recruited three of the police officers charged over the assault.
Local reports said the military also sheltered a soldier charged over the same incident and prevented him from being arrested.
Groenewald, who had been pushing for those involved to be prosecuted, said the military was stopping him from doing his job.
“The fact is I don’t agree with the way they’re interfering with policing,” he told the ABC.
“I’m a true-blooded police officer and I’m not satisfied with the way that they’re interfering in policing.”
Groenewald served for more than 40 years in South Africa before accepting the role of Fiji police commissioner.
He will be replaced by Lieutenant Colonel Sitiveni Qiliho, land force commander of the Fiji military.
In a statement, the Fiji government said Groenewald was leaving for “personal and family reasons”.
Following advice from Prime Minister Frank Bainimarama, as the chair of the Constitutional Offices Commission, Fiji’s President had appointed Colonel Sitiveni Qiliho as the Acting Commissioner, the government said.
Yesterday, Qiliho defended the military’s decision to hire the three police officers facing criminal charges, including one who is a suspected rapist.
They had been abandoned by the police after they were stood down over the assault charges, Colonel Qiliho said.
“They haven’t been convicted yet but unfortunately the police force has abandoned them.
“They were working for the Fiji police force and they were working with military officers. Now we will stand by our men and women through thick and thin. We’re not going to abandon them.”
Colonel Qiliho says the military’s lawyers will represent the men in court and they will continue to appear as required.
Last week, the lawyer acting for a Fiji soldier charged over the same assault disputed the prosecution’s claim that police unsuccessfully tried to arrest him at the military barracks.
The soldier, Pita Matairavula, appeared in court a week ago and was remanded in custody after missing two court summons in Suva last month.
- ABC/RNZI