Mr Pritchard is on leave from Australian Border Force. He spends most days on the couch in his Perth home. He enjoys virtually nothing, and contemplates suicide often. A child's cry triggers sickening flashbacks.

His wife Kathy is beyond desperate; sometimes suicidal herself. "Border Force broke my husband," she said, describing their life as "pure, torturous hell".

Mr Pritchard's experience is not a one-off. Over the past year, The Sydney Morning Herald and The Age have uncovered a troubling culture inside the border protection agency overseen by Home Affairs Minister Peter Dutton. Bullying and harassment have been rife, and officers suffering mental illness often go without adequate help.

The workplace problems have contributed to a string of suicides. The latest occurred last month when a Border Force officer took his life on a patrol boat off the Queensland coast.

Border Force deputy commissioner Justine Saunders said her organisation was examining Mr Pritchard's case.

"The mere fact that we have the family of a member reaching out says to me there is more work to be done in this space," Ms Saunders said.

Mr Pritchard's terms of employment prohibit him from speaking publicly about his ordeal. But his wife of 23 years is sharing the harrowing story, hoping it might get her husband the support he needs.

Working as a customs officer for ABF and its predecessor in Western Australia, Mr Pritchard boarded foreign ships in port. He scoured the computers and mobile phones of crew in search of illegal material such as child pornography.

He cannot forget the images he found of sexual abuse against children - mostly babies and toddlers.

Mrs Pritchard said her husband saw "images of babies under 12 months being raped".

"I see him become visibly distraught when flashbacks occur. He says he can see the children's faces and the deplorable acts," she said.

Mr Pritchard is also haunted by the day in 2005 when he boarded a foreign freight vessel at a Fremantle port. Three stowaways had been discovered in the ship's cargo hold; two of them were dead. Empty water bottles lay beside their parched corpses.

Mr Pritchard saw "mummified bodies of grown men gasping for their last breath", his wife said.

"He still smells their decomposing flesh ... their mouths were open wide," she said.

"Mike gets flashbacks ... he can still recall the smell of death and the looks on their faces."

Mrs Pritchard says her husband has also been bullied and intimidated at work, and in 2013 almost choked during a training exercise gone wrong.

Mr Pritchard kept showing up to work each day. But on a week's leave last year he had a personal reckoning: he was overwhelmed and traumatised. He has not returned to Border Force since.

So began the couple's months-long battle to make Mr Pritchard well again. Help has been slow coming.

Comcare, the federal government's workplace insurer, has so far refused to recognise Mr Pritchard as having post-traumatic stress disorder, despite several doctors treating him for the condition. He is receiving medical treatment but cannot access the high-level care he needs, leaving his wife to cope virtually alone.

A Comcare spokesman said it "acknowledges there are sometimes issues in the management of claims and we take active steps to improve support for injured workers where this occurs".

Mrs Pritchard, a teacher, has often returned from work to find her husband crying on the couch. He has been taken to hospital after threatening to kill himself. And after 10 months on leave his pay was cut by a quarter, putting a strain on the couple's finances.

"Mike was absolutely broken - beaten mentally and simply unable to function as a normal person," Mrs Pritchard said.

Responding violently to a nightmare one night, Mr Pritchard accidentally struck his wife in the head as she slept. The force compacted her neck vertebrae; she now sleeps on the bedroom floor.

Mrs Pritchard has reached breaking point; at times suicidal herself. Now on mental health medication, she is furious and exhausted, and pleading for help.

"Mike is starting to realise he will never really get better. I'm angry with Border Force for letting it happen, and I know there are other [officers] who are in the same headspace as Mike," she said.

This publication has also spoken to the former colleague of a Border Force recruit in Melbourne, Jayda Thomas, who took her life in August 2016. Ms Thomas had written a suicide note alleging problems at work, and was also believed to have been experiencing personal issues.

Jennifer Blais said she and Ms Thomas failed an "unrealistic scenario exam" and were told they probably would not graduate, despite having passed several other exams and spent six months training.

The women waited months for a final decision, during which time they were assigned menial tasks. "Every day we would ask for an update, no one knew what was happening, we were just left in the dark ... and I guess that's when Jayda lost faith and courage," Ms Blais said.

"She was crying all the time, looked anxious and worried as well as angry ... She then became visibly depressed. I was too."

Ms Blais, who now works elsewhere in the public sector, said she has "never recovered from Jayda's death".

"I still see a [psychologist] for what happened to me at ABF ... I can't stop reliving everything that happened. I'm still so angry."

As reported in December, a Perth-based Border Force officer, Michael Bradley, was experiencing problems at work and elsewhere before he died by suicide last year.

It is also understood that an officer who died on the night of June 18 took his own life.

The man, believed to be from Canberra, died while serving on a patrol boat in the Torres Strait. Sources say the man was a father of two whose partner was pregnant.

Community and Public Sector Union deputy national president Lisa Newman said Border Force members wanted a mental health strategy that recognises "the specific challenges of their work".

She said staff morale had been "driven ... into the ground" by a protracted bargaining dispute and lack of consultation about workplace change.

Ms Newman said some workers who suffered trauma did not seek help because they feared being excluded from on-water assignments, and subsequently losing pay allowances.

In response to that issue, Ms Saunders said Border Force was reviewing remuneration policies "to ensure they are not an impediment to members speaking up and seeking support".

The Department of Home Affairs - which includes Border Force - said it took the wellbeing of its employees very seriously.

Staff were offered a confidential support and advice service, and Border Force works with community support organisation Fortem Australia.

"We adopt a range of measures to protect staff and are always on a continuous improvement cycle to appropriately address challenges that officers are faced with," the department said in a statement, citing measures such as wellbeing seminars, resilience training, staff counselling and case management.