Victoria's chief police commissioner is confident a swearing in bungle will not impact any more cases, after a man walked free from jail over the issue.
The blunder, revealed late last month, was caused by an administrative oversight of the laws and resulted in more than 1000 officers being unlawfully sworn in.
It means those officers made arrests, pressed charges and issued orders without valid powers from July 2014 to August 2021.
The issue was aired in Ringwood Magistrates Court on Monday, where a man was released from custody after his case was struck out.
The Herald Sun reported the man, who was charged with weapon and drug offences, successfully argued his arrest and charges were invalid as the officer involved was wrongly sworn in.
Victoria Police Chief Commissioner Shane Patton said the amount of time the man spent on remand was also a factor in the magistrate's decision.
"That person had been on remand for nearly six months, 178 days, and we had sought to adjourn the matter so we could further argue the case," he told ABC Radio.
"The magistrate has made a comment to the effect that the charges, really for the amount of time he's already spent in jail he's not going to get any more, and so to adjourn it wouldn't have been fair."
A Victoria Police spokesman said it was reviewing the case to decide whether it will appeal the magistrate's decision.
Mr Patton said he had no fear that other cases will be impacted and urgent retrospective laws, which passed through state parliament on Tuesday, will resolve all outstanding issues.
"I've been briefed on the retrospective legislation, that will put beyond doubt any issues in any of these cases whatsoever," he said.
Attorney-General Jaclyn Symes said the legislation was based on the best legal advice and was confident it would stand up to legal challenges.
"But of course, like any law, it's open to lawyers to take the challenge to the court and that may indeed happen," she said on Thursday.
The bill, which is awaiting royal assent from Victoria's governor, is expected to become law on Friday.
The legislation dictates that any powers or duties performed by wrongly sworn police between July 2014 and August 2021 were exercised validly.
AAP understands when the bill kicks in the admissibility of evidence and legal liability of police officers will not impacted by the administrative error.
