Friday, March 22, 2019 (and into early hours of Saturday, March 23)

* Male staffer of Defence Industry Minister Linda Reynolds and media adviser Brittany Higgins turn up at Parliament House. Ms Higgins appears heavily intoxicated.

* Security officer signs in the pair (it is speculated at least one of them did not have a security pass).

* Security officer takes the pair to the ministerial wing, and unlocks minister's office door at the male staffer's request.

* Security officer leaves.

* Incident occurs.

* Male staffer leaves the office while Ms Higgins remains there.

March 23

* Security officers check on Ms Higgins' welfare very early morning.

* They find her disoriented and half-naked in the office.

* Department of Parliamentary Services informs the Department of Finance (which administers Parliament House offices) two staffers had been found after-hours in breach of rules.

* Discussions are held over whether the office should be cleaned before the return to work on Monday.

* Cleaners entered the office in the late afternoon at the request of the Department of Finance. It was described by DPS as a routine office clean.

March 26

Ms Higgins is called to a meeting with Senator Reynolds' chief of staff over a "security breach". The male staffer is called into a separate meeting.

March 27

DPS secretary provides a report to the minister on the security breach.

Ms Higgins meets with police unit at Parliament House.

Police find there is no criminality involved in the office clean (such as interfering with a crime scene) as there had been no disclosure of sexual assault on the day of the incident.

April 1

Ms Higgins meets with Senator Reynolds in the office where the incident occurred. The minister makes it clear Ms Higgins would have her full support in whatever action she wanted to take.

Alleged perpetrator is dismissed from Senator Reynolds' office over the "security breach". Prime Minister Scott Morrison's chief of staff John Kunkel was part of the dismissal process but was unaware of rape allegations. Senator Reynolds says she sought advice on the dismissal from Ministerial and Parliamentary Services.

April 4

Senator Reynolds and her chief of staff meet with an AFP assistant commissioner to discuss what AFP describe as "allegations of sexual assault". Ms Higgins is not present at the meeting.

April 8

Ms Higgins goes to Belconnen police station. Police say they are having trouble getting security camera footage from Parliament House.

April 11

Federal election is called.

April 13

Ms Higgins tells police she won't continue with the complaint.

April 29

Ms Higgins is asked by AFP whether she is not continuing the complaint because she wants to protect the male staffer.

June

Post-election Ms Higgins goes to work for minister Michaelia Cash.

A number of stories are published about the workplace culture in Parliament House.

Senator Reynolds' former chief of staff Fiona Brown goes to work in the prime minister's office.

October 18

Media inquiry lodged with Senator Reynolds' office and AFP about the incident.

October 19

AFP contact Ms Higgins about the possibility of the media inquiry being raised at a Senate estimates hearing on October 21. The ACT police commissioner prepares notes to go into the AFP commissioner Reece Kershaw's briefing pack ahead of the hearing.

Michaelia Cash contacts Ms Higgins to leave a voicemail saying: "Just remember we are with you every step of the way".

Senator Cash's chief of staff meets with Ms Higgins to say they will try to quash the media story.

2020

November 9

Four Corners' Canberra Bubble program goes to air, raising concerns about workplace culture problems in the coalition. Prime Minister's principal private secretary Yaron Finkelstein checks in with Ms Higgins (the prime minister disputes this).

November 12

Public sector union writes to the finance department, which responds four days later agreeing to a culture and workplace policy review.

2021

January

Senator Cash seeks to encourage Ms Higgins to stay on staff, offering a relocation to Queensland, but she declines.

February 5

Ms Higgins resigns from Senator Cash's office citing ongoing trauma over the March 2019 incident.

Feb 12

Mr Morrison is made aware of incident.

Feb 15

Ms Higgins tells her story publicly to news.com.au and The Project. She says she has plans to take up the matter with police.

Feb 16

Mr Morrison offers apology in parliament, as does Senator Reynolds. Two reviews are launched: one by Liberal MP Celia Hammond to work on improving behaviour within coalition ranks; and a second by Stephanie Foster, the deputy secretary of the Department of Prime Minister and Cabinet, to advise on how to improve formal support processes.

(Sources: news.com.au, Senate Hansard, Department of Parliamentary Services)

Australian Associated Press