After the three door-knocks that signal her arrival, Justice Fullerton usually zooms up the stairs and into her seat.

Her enthusiasm and dedication for her work is evident, even in a complex, convoluted and trying case like that of Lian Bin "Robert" Xie.

As the second judge in the Xie matter Justice Fullerton had her work cut out for her, having to deal with a hung jury at the end of the third trial, which ran for most of the 2015 law term.

Upon hearing of the impasse in the jury room, Justice Fullerton told the jurors: "The law should not be something you are fearful of."

During that trial, she expertly mediated dogged legal arguments between Crown prosecutor Mark Tedeschi, QC, and defence barrister Graham Turnbull, SC, often with a firm rebuke of "gentlemen".

In the final days of the fourth trial, defence barrister Robert Webb told Justice Fullerton he would not pursue submissions he made, and which she had considered over her Christmas break.

"That really made my Christmas," Justice Fullerton said, out of the presence of the jury.

"I'd wipe that smirk off your face, Mr Webb. Let the record reflect that insight."

Mr Webb denied he had smirked and asked her to withdraw her comments.

"I will not," the judge responded.

Justice Fullerton may have developed her disciplinarian skills in her first job as a teacher at Port Melbourne Primary School in the mid-1970s.

According to a speech given by Michael Slattery, QC, at Justice Fullerton's swearing-in ceremony in 2007, she decided to make a career switch while working on a kibbutz in Israel in the late 1970s, and studied at Monash University and UNSW.

Justice Fullerton later became a barrister in Sydney, with stints as a prosecutor and defender, and was known for her meticulous cross-examination skills.

Justice Slattery said: "One of your cross-examinees left the witness box and whispered to his counsel, 'She's scary'."

Before her appointment to the bench, Justice Fullerton defended Rodney Adler, the disgraced businessman jailed for providing false information in the lead-up to the collapse of HIH Insurance, and corporate fraudster Tony Oates.

She was also the counsel assisting the coroner at the inquest into the death of TJ Hickey, an Aboriginal teenager who was impaled on a fence in Redfern, and whose family blamed police.

"You were a charismatic advocate," Justice Slattery said. "Your presence changed every courtroom in which you appeared. Wherever you were, you were the undisputed Queen of the Bar table."

Since 2007, she has presided over many high-profile cases, including the trial of Paul Mulvihill​, whom she sentenced to a maximum 29 years' jail for the stabbing murder of his former lover Rachelle Yeo.

In 2013, Justice Fullerton sentenced Philip Nguyen to a minimum seven years' jail for the manslaughter of police officer Constable William Crews.

The then Attorney-General Greg Smith quickly indicated he would look at options to appeal the sentence, which the Crews family felt was too short, and Nguyen's jail term was almost doubled on appeal.

Before the fourth Xie trial this year, Justice Fullerton oversaw the trial of Adeel Khan, who was jailed for a maximum 40 years for the fatal Rozelle shop explosion.