Relatives of American mathematician Scott Johnson say the uncertainty created after attempts to halt sentence proceedings by a man who admitted to his murder, is "excruciating".
Scott Phillip White entered the unexpected guilty plea in the NSW Supreme Court during a pre-trial hearing in January, after being charged in 2020 and denying responsibility for Mr Johnson's death.
It marked a significant development in a decades-old Sydney mystery after Mr Johnson, then 27, was found at the base of cliffs in Manly in 1988.
White, 51, has begun appealing his conviction after his lawyers unsuccessfully attempted to vacate the plea by calling into question its integrity, citing cognitive impairment, his failure to inform them prior and his state of "extreme agitation" on the day he made it.
Justice Helen Wilson yesterday dismissed an application to halt sentence proceedings, due to take place early next month, until after the appeal and said delaying the matter would be "bordering on the unconscionable".
In an affidavit to the court, the officer in charge of the investigation, Detective Chief Inspector Peter Yeomans, described the "considerable emotional courage" of Mr Johnson's siblings as they prepare to fly from the United States to face White in court.
He said Rebecca Johnson expressed concerns as she compiled a victim impact statement.
"I feel like I am living in the loss and trauma every hour," Ms Johnson said, according to the detective.
"Writing the statement, preparing for this hearing, contemplating what it will be like to be there, in the room with Scott's killer, is a tremendous emotional toll.
"The idea that we/I will be simultaneously preparing to go and have this ending and knowing that the sentencing hearing may not happen, so we'll have to do it again, is excruciating."
Detective Yeomans said Mr Johnson's brother, Steve Johnson, expressed similar sentiments following White's "emphatic" guilty plea.
"To deny the family this and have them try and prepare themselves to come back for another date would cause unnecessary and unimaginable torment to the Johnson family," Detective Yeomans wrote.
"[It would] add to the heightened trauma they are already enduring, as well as significant financial cost."
Detective Yeomans said the family had been fighting for justice for their brother for more than 33 years.
He said Steve Johnson was "instrumental" in having the matter reinvestigated, including two coronial inquests, after it was initially ruled by police to be a suicide.
The family always maintained Mr Johnson was the victim of a gay hate crime.
The court yesterday heard White now "maintains his innocence", with his defence barrister describing the situation of sentencing a person in such a position as "unusual".
In dismissing White's bid to stop his sentence hearing, Justice Wilson noted a Crown submission that delaying it until after the appeal would mean a wait of "literally years".
She acknowledged it meant that if the decision to accept the guilty plea is overturned, the sentence proceedings would have been "futile".
White's sentence hearing is expected to proceed on May 2.
