NSW Police may be forced to take a more cautious approach with their investigation tactics after being ordered to pay $1.5 million in damages to a former suspect in the disappearance of toddler William Tyrrell.
Eight years ago, Strike Force Rosann was set up to find out what happened to William, who vanished from his foster grandmother's home, but this week its tactics were admonished in the Supreme Court.
Justice Ian Harrison found the high-profile team's malicious pursuit of washing machine repairman Bill Spedding "never should have occurred".
Mr Spedding was never charged over William's disappearance but, in 2015, the strike force — led by then-chief inspector Gary Jubelin — charged him with historic child sex offences dating back to 1987.
He was later cleared of those allegations at trial.
Mr Spedding then sued the force for malicious prosecution, arguing he was wrongly charged with sexual assault to place pressure on him as a suspect in the unrelated disappearance of William.
His win in court on Thursday has experts predicting the police may now hesitate before using the same strategy in future investigations.
Internationally renowned criminologist Xanthe Mallett from the University of Newcastle said the court's decision could prompt internal change in the force.
"Putting pressure on suspects using additional charges for unrelated matters is something we've seen before and since," Associate Professor Mallett said.
"[But] I think it will cause police forces [to] pause when employing some of these strategies in the future.
"I think it may make them more cautious with some of their tactics now that they've been openly criticised for some of the more potentially cynical aspects of this case."
Justice Harrison said the historical sexual assault allegations levelled against Mr Spedding were old and discredited and noted that no one from the police had apologised to him.
However, he was not the only suspect in the Tyrrell case that Strike Force Rosann detectives tried this tactic on.
A magistrate last month found William's foster mother not guilty of lying to the NSW Crime Commission about hitting a child, not William, with a wooden spoon.
Detectives admitted in open court that this charge was laid, at least in part, to pressure her into confessing to offences relating to William's disappearance.
The current team on Strike Force Rosann believe William died accidentally before his foster mother covered it up by disposing of his body, the court was told.
William's foster mother has repeatedly denied any involvement in his disappearance.
She remains before the courts on charges of assault, intimidation and fraud.
Last month, she urged police to focus their efforts on finding William, something echoed by Mr Spedding yesterday.
"I hope that the incorrect focus upon me, as a suspect, has not irreparably damaged the prospect of solving this mystery," he said outside court.
The latest ground search for William in November 2021 turned up nothing, despite police being certain they knew where he was buried.
In the year since, there have been no breakthroughs and no insight into the strike force's progress with William's case.
No one has ever been charged in relation to William's disappearance.