A former constable sacked from the police after he subjected his girlfriend to a "sustained" beating was able to train as a firefighter - stunning and angering his soon-to-be colleagues.

In October 2015 Lomitusi Lomi was convicted of injuring with intent to injure after he repeatedly punched, kicked and dragged his girlfriend during the brutal attack.

He was then fired from his job as a constable.

The Herald has learned that Lomi is in the final stages of his training with Fire and Emergency New Zealand and was set to be posted to a suburban Auckland station to work as a professional firefighter once he graduates.

However according to FENZ employment policy, his conviction means he could never work for the organisation.

After the Herald made inquiries, FENZ stood Lomi down and an investigation is under way as to how he was ever taken on as a recruit in the first place.

FENZ director of people and capability Brendan Nally said a final decision on Lomi's employment would be made following the investigation.

"Firefighters are in a position of trust in their communities," he said.

"As such, I expect all our people to display the highest levels of integrity and respect."

"I can confirm that a recruit is currently on stand down while we investigate further.

"The details surrounding his recruitment, interview and vetting process still need to be clarified before any further decisions are made.

"However, at this point in time, it is prudent to stand the individual down while the matter is sorted."

A source said FENZ policy on people with convictions was clear - and should have prevented Lomi from being recruited.

According to the policy person cannot join FENZ if they have been convicted of a sexual offence, theft, fraud, perjury or other dishonesty offences; or offences punishable by two or more years in prison.

His conviction was punishable by five years in jail.

Even though he did not serve time, the fact that he was convicted of an offence that carried that maximum penalty should have meant he was ineligible.

Furthermore, FENZ security screening policy sets out the rules for screening applicants and is supposed to be applied when appointing a new employee or volunteer.

"Security screening is the process of requesting information from the police about any previous criminal activity and any current associations a person may have," the policy states.

"This information is then used to determine acceptability for employment or engagement with us."

Existing employees can also be screened if it comes to FENZ's notice that they have been "charged with, or convicted of, a criminal offence".

"All appointments are conditional on the applicant getting the necessary security clearance," the policy states.

Staff were calling for all recent recruits to be re-checked given Lomi was able to get so far through the recruitment process.

"It makes you wonder who else has been put in the job who shouldn't have been," the source said.

He told the Herald that many FENZ staff were outraged by Lomi's recruitment.

"It's not going down very well in the ranks," he said.

"They are really unimpressed by it, it's raised a lot of question."

FENZ staff felt that Lomi was "not the type of person" to be a firefighter.

"It's a very, very bad look," the source said.

"Firefighters are the most trusted profession with statutory powers that can put staff into pretty complicated positions - it's a job for people with integrity and I don't feel that he has that.

"I'm all for giving people second chances, but this isn't the job for someone with this type of conviction."

The source said staff, particularly those working in the station where Lomi was set to work, were outraged by the situation.

"The female staff are mortified by it and say they will feel very uncomfortable working with him," he said.

"Not a single staff member I know of is happy with it or comfortable with it.

"They all feel it's detrimental to the organisation… they don't want to see it brought down by someone like this."

It is understood Lomi declared his conviction - but not until the final stages of the recruitment process. 

"When applying for a firefighter role, all applicants are required to declare any previous criminal convictions," Nally said.

"While a conviction won't necessarily preclude a person from employment, it will be taken into consideration during the process.

"Firefighting demands absolute faith and confidence from the communities we serve and our colleagues.

"I am committed to establishing the facts so I can give assurance to the community, and our people, that only the right individuals will be appointed to such a trusted position."

In 2015 Lomi was blasted by his sentencing judge for his violent attack.

The court heart that Lomi, then 24, and his girlfriend of more than four years returned home from a night in town and after a verbal argument he punched her in the head.

As she attempted to escape he dragged her back onto the bed by her pyjama top.

There were further kicks and punches as she cowered in the corner of the room, her hands covering her face to protect herself.

Lomi then followed her to the lounge and ripped off her top before she managed to grab her car keys and flee.

Lomi was stood down from his duties as a constable in West Auckland while his case was before the courts.

After he was convicted and police completed an internal police investigation he was fired. 

The charge carried a maximum of five years' imprisonment - but Lomi was sentenced to 120 hours community work and 18 months intensive supervision.

"Men who use their strength to beat women are, quite frankly, cowards," said Judge Nevin Dawson at sentencing.

"You had the chance to pull back but you didn't, you continued.