Brittany Higgins and Bruce Lehrmann will have to wait months before another trial takes place over an alleged rape inside Parliament House.
A new trial date has been set for February next year after the judge presiding over the case declared a mistrial and discharged the jury.
Jurors were still deliberating and had not reached a verdict.
After more than five days of deliberations, Chief Justice Lucy McCallum revealed one of the jurors brought information into the jury room which had not been presented as evidence in court.
Despite the juror in question claiming the information had not been used or relied upon, the chief justice said she had no choice but to abort the trial.
"This is an unexpected and unfortunate outcome," she told the court.
"I have heard an explanation and it may be that no harm has been done. But that is a risk I cannot take."
During the trial and deliberation period, Chief Justice McCallum gave jurors at least 17 warnings against conducting their own research on the case.
In her reasons for dismissing the jury, she revealed the misconduct was "inadvertently discovered" by court officers on Wednesday afternoon.
During a routine tidy of the deliberation room, one of the sheriffs accidentally bumped one of the juror's clear document folders onto the floor.
The chief justice said when the officer picked up the box, they noticed part of the title page of an academic research paper which had not been provided to the jury during the trial.
Upon further investigation it was discovered the topic of the paper was sexual assault. It included information about quantifying the number of false complaints.
"It is beyond question the conduct of a juror is such to abort the trial," Chief Justice McCallum said.
Bruce Lehrmann was being tried by the ACT Supreme Court, charged with sexual intercourse without consent.
He pleaded not guilty.
Ms Higgins addressed the media outside the court after the jury was dismissed.
"I chose to speak up," she told reporters.
"Speak up against rape, speak up against injustice, to speak up and share my experiences with others.
"I told the truth no matter how uncomfortable or unflattering to the court. Today's outcome does not change that truth."
Defence lawyer Steven Whybrow also spoke to reporters.
"We're disappointed by what's happened, but it would be inappropriate and irresponsible to say anything at this stage," he told reporters.
Lehrmann remained silent.
A new trial has been set down for February 20 and Lehrmann will remain on bail.
In her closing remarks, Chief Justice McCallum urged against reporting the case to ensure a fair trial and to provide Ms Higgins with some respite.
"The accused is just that. He is a person that stands accused," she said.
"The fairness of his trial will undoubtedly be impaired or at risk if people continue to report on this case with the frequency that has occurred.
"I would expect after reporting the outcome of today that reporting of the matter should fall silent so the accused can have a fair trial and Ms Higgins can have some respite from the intense glare of the media that has been pervasive in this trial."
In light of this, Mr Whybrow criticised Ms Higgins' statement outside court and referred her comments to the Australian Federal Police.
He said Ms Higgins and her team were inside the courtroom when the chief justice discharged the jury and spoke about people making statements that could prejudice a fair trial.
The jury previously sent notes to the court indicating it was unable to reach a unanimous verdict on the rape allegation.
The chief justice encouraged them to persevere each time.
Ms Higgins alleges Lehrmann raped her in the parliamentary office of Linda Reynolds when they worked for her as defence industry minister in March 2019.
He denies any sexual interaction.
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