A Department of Defence military police report from July this year described how the staff member was sacked from the force's Joint Operations Command centre after they pleaded guilty to drug possession and supply.

The Joint Operations Command is based in Bungendore, about 40 kilometres east of Canberra, and is a high-security site responsible for coordinating defence force activities across the globe.

Senior defence officials were told about the staffer's arrest in December last year, according to the report, before the staff member appeared in the ACT Magistrates Court.

"At that time the member was recorded to have entered a plea of guilty and was later convicted on two charges, possession of an illicit substance and sale and supply of an illicit substance," the report read.

The military police reports were released by the Department of Defence under freedom of information laws.

The military police are responsible for maintaining discipline under the military justice system.

"Offences by ADF members are prosecuted...within the military justice system when the offence substantially affects the maintenance and ability to enforce service discipline in the ADF," the defence force's website said.

"Otherwise, criminal offences or other illegal conduct are referred to civil authorities, such as the police."

The military police reports also described how an employee at the elite Duntroon Royal Military College was sacked after admitting to steroid use.

"[He] admitted to using testosterone and nandrolone decanoate to aid his physical recovery from a persistent injury and to prevent further injury," service police wrote in September 2016.

"[He] also admitted that he only came forward to admit his use of steroids because he had been tested earlier that day."

The military police also investigated allegations in November 2015 that a member of a defence force cricket team visiting Canberra had taken MDMA during a night out.

"During [a] conversation he allegedly stated, 'I'm drunk and high on ecstasy', or words to that effect," the military police report read.

The matter was closed after military police were unable to find any first-hand evidence of drug use.

The Defence Department has recently begun an expanded testing program, which utilises hair and saliva samples to broaden the detection window for illicit drugs.

A spokeswoman for the Department of Defence has previously said at least 25 per cent of personnel were tested for drugs every year.

At Duntroon this would include both staff members and cadets, she added.

"The use of prohibited substances is not compatible with an effective and efficient ADF and has the capacity to undermine safety, discipline, morale, security and reputation.

"All ADF personnel are subject to the prohibited substance testing program, which allows for testing of ADF members anywhere and any time."

Defence's prohibited substance testing program, introduced in 2005, typically relies upon urine testing to detect drugs such as cannabis, methamphetamine, MDMA and cocaine.

Hair and saliva testing will be trialled between October 2017 and July 2018 because these allow drug use to be detected over a window of up to three months.