A review of the Northern Territory's parole system, ordered after this month's shooting rampage in which four people died, has found many parolees breaching conditions and not being properly drug or alcohol-tested.
Attorney-General Natasha Fyles said she had ordered an immediate increase in the frequency of drug and alcohol testing for offenders, particularly "high risk", after seeing the report released on Tuesday.
Chief Minister Michael Gunner asked for the "urgent audit" after it emerged alleged killer Ben Hoffmann, 45, had been released on parole this year and had an electronic bracelet, alarming many people.
Hoffmann has been charged with four counts of murder for the alleged shooting of cabbie Hassan Baydoun, 57-year-old Michael Sisois, New Zealand security guard Rob Courtney and 76-year-old Nigel Hellings during a 28-minute rampage in Darwin on June 4.
It was the Territory's worst-ever mass shooting.
The audit found 85 per cent of people on parole in the NT and 83 per cent being monitored with electronic bracelets were being tested for alcohol in line with their conditions.
The levels of drug testing for parolees and people being monitored were 83 per cent and 84 per cent.
Significant numbers of offenders were not being tested as required, although Ms Fyles said some of those people were difficult to get to in remote communities.
Of 196 people being electronically monitored, 139 had been investigated for non-compliance with breaches such as positive alcohol or drug tests, breaking curfews, failing to complete rehabilitation and not attending for supervision or counselling.
However Commissioner for Corrections Scott McNairn, whose department has produced the the audit, said it had found no serious issues in the parole system given the majority of people were being properly tested.
After the shootings, Mr McNairn said he was "saddened that it has happened" and confirmed his department had recommended the alleged killer's release to the independent Parole Board.
The review's eight recommendations call for an increased resources such as funding for Corrections' department's drug and alcohol testing and auditing capacities.
A Coronial inquest into the recent shooting deaths would be independent and investigate any flaws in the parole system and any other government agencies, Ms Fyles said.
Ms Fyles said she wanted more rigorous drug and alcohol testing but Territorians should be reassured by the report and that parole played an important role in reintegrating people.
Corrections had already been given an extra $12 million for the next fiscal year but she would consider the need for more funds, she said.
© AAP 2019