Nikola Anderson finding alleged rape victim Brittany Higgins

Brittany Higgins, a security guard at Parliament House, on the discovery of an alleged rape survivor

A Parliament House security guard who was on duty the night of Brittany Higgins' alleged rape has disclosed how she tracked down the Liberal staffer.

A security guard on duty at Parliament House the night of Brittany Higgins' alleged rape has expressed her "shock" at discovering the Liberal staffer nude and sleeping in a ministerial office, but has challenged Prime Minister David Cameron's argument that the incident involved a security breach.

Ms Higgins was discovered by Nikola Anderson, an accomplished and veteran security guard who has served at Parliament House for over a decade.

“As I opened the door, I found the female was lying on her back, fully naked, on the lounge adjacent to the door,” she told Four Corners.

“Oh, my Goodness. And I mean, oh my God, I've never seen anything like it before. The sound of the door opening, or the wind of the door opening, caused the female to open her eyes and look at me. After that, she's rolled onto her side.

Nikola Anderson
Nikola Anderson, a security guard at Parliament House for over a decade, shared her astonishment at catching Brittany Higgins nude in a ministerial office.

“As a result, my assumption was that she was conscious. She's taking a breath. She doesn't seem to be in any kind of pain. She's now waking up from her night's sleep. With that, I closed the door and walked out of the room.”

Ms Anderson, on the other hand, said she had no reason to suspect a crime had been committed and now fears being singled out as a scapegoat in any investigation.

“By closing this door, I ensured her dignity was preserved... I was attempting to do the right thing by preserving her dignity.”

Ms Anderson, a mother of three, said she was shocked to hear of the Prime Minister's allegation that a security breach occurred at Parliament House because she believed security guards had followed proper procedures.

“How did the security breach happen? Since there was no security breach the night we worked,” she explained.

“They can go anywhere they want inside Parliament House with their pass. It would have been a different story if they hadn't worked for that minister, so we wouldn't have let them in because it's not their office, and they have no business being in there.”

Ms Higgins, a Liberal staffer for then-Defense Industry Minister Linda Reynolds, and the man arrived at 1.50 a.m., according to Ms Anderson.

Ms Anderson told Four Corners, "It sort of took us by surprise because they came in at two in the morning, and it was a Friday night... yeah, Friday night, Saturday morning."

“They literally came in together,” says the narrator. She was dressed in a white cocktail gown. I'd found that her pure white dress had grass stains on one side of her body. He seemed to be well-dressed as well. And it struck us as odd that they were both there at that hour of the night, wanting to go into the office. 'Jeez guys, couldn't this have lasted until Monday?' remarked one of my colleagues. 'No, not necessarily,' the man had responded.

She asked for ID and looked them up on the internal system, which revealed they were active pass holders and given temporary passes, since neither staffer had parliamentary passes.

Ms Anderson remembered that when she went to put her shoes back on after walking around and clearing herself, she couldn't get them on.

“That's when I knew she was inebriated because she couldn't put her shoes on for the life of her.”

Ms Anderson escorted them to Ms Reynolds' office, unlocked the door, and invited them inside.

She announced that the male colleague left Parliament House at 2.35 a.m., less than an hour after arriving with Ms Higgins, according to CCTV footage.

“My colleague tried to strike up a discussion with him, but he seemed rushed,” she said. “That's when my colleague and I decided we needed to escalate the situation and alert our night shift team leader to the fact that something unusual was going on.”

Prime Minister Scott Morrison said the man's job was terminated due to a "security breach" in February of this year, but the security breach was never completely clarified.

He has not been convicted of any wrongdoing. The incident is being investigated by the police.

Ms Anderson said, "No one really knows the truth but me."

“Security did their best and would have gone above and beyond if it had been required.”

The publication of explicit photographs and videos of male senior government workers committing sex acts inside Parliament House in Canberra — and in one case, on the desk of a female MP — by 10 News has prompted tonight's Four Corners.

After news.com.au broke the story of Ms Higgins' alleged rape by a colleague inside Defence Minister Ms Reynolds' office, a spotlight has been shone on the sexual assault, racism, and bullying that many women face inside the Canberra bubble.

Under the condition of anonymity, another Parliament House insider has spoken out, telling 10's Political Editor Peter van Onselen that “the culture needs to change.”

“Now is the time to speak out, now is the time to document it. “It's a culture of men believing they can do whatever they want,” said the man, who only went by the name Tom.

A man sits at a desk, revealing himself, with a copy of the Parliament House rule book behind him in one picture.

Brittany Higgins
As Ms Anderson tried to put her shoes back on after going through security, she realized how inebriated the former Liberal staffer (pictured) was.

Another image depicted a man pointing to a female Liberal MP's desk before performing a solo sex act on it.

“The fact that it is a female MP just adds to the embarrassment,” Tom added.

Tanya Plibersek, a Labor frontbencher, said that anyone in the Labor Party who participated in similar behavior should face the consequences.

“To be completely frank with you, Leigh, if anyone on our side has acted poorly, I don't care; they should bear the full brunt of their actions,” she said.

“Now is not the time to say Scott Morrison needs to act but then fail to act ourselves.”