A woman doesn't know why she allegedly walked under a plane on the tarmac at Canberra Airport and described her own actions as "bizarre", a court has heard.
Rejoice Alfred, 20, was suffering from psychosis when she allegedly ran through security, activated fire alarms and entered a dangerous restricted area last November.
On Monday, magistrate Ian Temby found the cause of this psychosis and the link with Alfred's mental health diagnoses was "entirely unclear".
As a result, the ACT Magistrates Court rejected Alfred's application to have the charges against her dismissed on mental health grounds.
"The medical evidence really is lacking in clarity as to how the conditions emerged and what caused the defendant's conduct on the day in question," Mr Temby said.
She is yet to formally enter pleas to entering airside areas without permission, and property damage.
Outside court, a supporter yelled and swore at this reporter while Alfred hid underneath a black coat.
In court, Alfred's lawyer, Paul Edmonds, argued his client's diagnoses of depression and post-traumatic stress disorder warranted her being diverted from the criminal justice system.
"There is little doubt that this young lady suffered some sort of psychotic episode on the day of the incident," he said.
"[Her] actions on this day were quite irrational and she was not thinking clearly at the time of the alleged offences."
Mr Edmonds argued there was evidence Alfred used marijuana but it was "unclear how much".
Prosecutor Samuel Carmichael argued the psychosis was drug-induced with a medical report making that diagnosis "undeniably clear".
"The nature of the mental illness seems to be almost intimately involved with the fact that the defendant had taken illicit substances prior to the offending," Mr Carmichael told the court.
"[The alleged crime] wasn't a simple act of wandering through the wrong door ... [Alfred] went through multiple layers of security was told multiple times to cease her conduct."
Ultimately, Mr Temby rejected the application and said "why she did it, she doesn't know and I don't know".
"The defendant herself describes her actions as bizarre," the magistrate stated.
Police documents allege on November 1, 2023, Alfred arrived at Canberra Airport and spoke to a Qantas staff member, repeatedly saying "have a nice day" and asking "how can I help you?".
She is said to have then walked over to a security screening point, and ran through it.
The documents state after failing to gain access to the aerobridge, she activated two fire alarms which disabled the security doors.
She then entered a restricted area "for the movement of incoming and departing aircraft", the documents allege.
"This area is restricted due to the extremely high risk of serious injury or death due to inappropriate movement of persons."
Alfred allegedly ran onto the tarmac where a Qantas aircraft with 100 passengers was parked.
She is said to have walked under the front fuselage of the plane for a short time before leaving.
Alfred allegedly ran back into the airport building and headed towards a taxi rank.
When police arrived she was sitting in the rear seat of a taxi.
Police documents state her "demeanour was poor" and she kept repeating the phrases "have a nice day" and "how can I help you?".
Alfred is set to return to court next month.
