The state's police leadership says the Northern Region is "over-represented" when it comes to officers on long-term sick leave and has a "very serious problem" retaining staff.
NSW Police Commissioner Karen Webb told a budget estimates hearing this week that one in five sworn officers on extended sick leave in the state were from the Northern Region, which stretches from the Hawkesbury River to the Queensland border.
Commissioner Webb said between 9 and 10 per cent of officers across NSW were on long-term sick leave.
Asked how many of those were in the Northern Region, she said: "I can take that on notice, but I think it might be 20 per cent, so it is over-representative of the rest of the state.
"It has been a trend for as long as I have known and worked in the Northern Region that the Northern Region does have a higher absentee rate, long-term sick."
The police force has about 17,000 sworn officers, which suggests about 1700 are off work on extended sick leave, including 340 in Northern Region.
NSW Police refused to disclose how many sworn officers worked in the Northern Command and what percentage of the state workforce they represented.
Police Association NSW vice-president Ian Allwood said the union was concerned about the number of officers off work.
Commissioner Webb told the estimates hearing that "there is a growing trend in psychological claims versus physical injury claims" among officers off work.
She agreed with a suggestion from Greens MP Sue Higginson that a "fair chunk ... of officers that have a complaint against the police, whether it is an IR or a civil complaint ... are often on sick leave as well".
Ms Higginson later told the Newcastle Herald that she was concerned many police might be on leave due to the "bullying" treatment they had experienced from their superiors.
The police force is facing a staffing crisis with about 1500 vacancies, prompting the state government to offer $30,000 pay for potential new recruits to attend the Goulburn training academy for 16 weeks.
Police Minister Yasmin Catley told budget estimates that Northern Region had a "very serious problem" with retaining officers.
Ms Higginson asked Ms Catley if she would investigate "reform internally" if "you had evidence before you of a number of police officers, particularly from the Northern Region, that are sitting in a system where they are wrongly persecuted for policing".
"This is the first time this has been suggested to me," Ms Catley replied.
"If systemic problems are raised with me, of course I will look at it and I will work with the commissioner."
NSW Police is trialling a mental health support program for officers called PULSE, which Commander Webb said had recruited 11 clinicians "located in geographical areas to service a small cluster of commands".
She said she hoped to have another 17 clinicians in place by early next year under the program, which is funded for five years.
"We did hear from officers over time that they couldn't get access to treatment or services when they wanted it, and so we are very optimistic that this will provide some respite so that officers can get access earlier," she said.
Deputy Commissioner David Hudson said the process of investigating complaints against police "can be clunky".
"I don't think it's streamlined enough, and we're working with Professional Standards Command to actually improve that," he said.
"I think the longer a complaint goes the more likely it is that the involved officer will be damaged in some way."
