The retrial of David Harold Eastman for the assassination of ACT police chief Colin Stanley Winchester has cost about $6.5 million, new figures show.
The former ACT Victims of Crime Commissioner said justice could not be measured in monetary terms.
Mr Eastman was on Thursday found not guilty of the murder after a five-month trial in the ACT Supreme Court.
The ACT government said costs associated with Mr Eastman's retrial, including pre-trial and other related proceedings, were about $4.1 million in 2017-18.
From July to the end of October, when much of the trial was held, the actual expenditure was about $2.4 million.
In the year leading up to the trial, the ACT Office of the Director of Public Prosecutions paid almost $900,000 to external counsel for the Eastman trial, the 2017-18 annual report shows.
The ACT Legal Aid annual report does not detail the trial's expenditure for the same period.
The figure is almost $900,000 cheaper than originally expected, after the government set aside $7.4 million for the retrial in the 2017 ACT budget.
A government spokesman said the cost had included funding for the ACT courts and tribunal, Legal Aid, the Director of Public Prosecutions and ACT Policing.
"The 2018-19 budget provided $6.2m for the costs of the retrial, which included rollover funding from 2017-18," the spokesman said.
Mr Winchester was shot twice in the head at close range as he got out of his car on January 10, 1989.
Mr Eastman was convicted and sentenced to life imprisonment in 1995, and was freed in 2014 after serving 19 years in jail.
During this time, Mr Eastman maintained his innocence and fought a number of legal battles from behind bars, including an appeal to the High Court in 1997, two inquiries, and other matters in territory and federal courts and tribunals.
His release came in the wake of an inquiry, headed by former Northern Territory Chief Justice Brian Martin, and his conviction was quashed by the full bench of the ACT Supreme Court.
The Canberra Times has previously reported that pursuing Mr Eastman has cost the taxpayers tens of millions of dollars.
Many of the costs had been met within the budgets of government-funded organisations.
Between the 2001 and 2004 budgets, an extra $1.5 million was provided.
Figures show the government paid more than $12 million for the Martin inquiry.
Former ACT Victims of Crime Commissioner John Hinchey - who represented the Winchester family outside court on Thursday - said a dollar figure could not be placed on justice.
"You can't measure justice in terms of money, particularly when a senior officer, deputy commissioner of the AFP, has been assassinated outside his home in cold blood," Mr Hinchey said.
"You must pursue justice, at all costs, to the end and that's happened.
"I only have admiration for the courage of our DPP, Mr Jon White, for bringing forward this re-trial."
ACT Attorney-General Gordon Ramsay said the justice system depended on an open and transparent trial, and this had occurred.
"This has been a lengthy and complex trial, and I thank the jury for their service on this matter. Decisions about pursuing a prosecution are matters for the Director of Public Prosecutions and made independently of government," he said in a statement.
"The government is committed to supporting our justice system to conduct fair trials. That support includes financial resources and legislation. We have an obligation to provide our community with transparent, accessible, and timely court services."
Shadow attorney-general Jeremy Hanson said: "Regardless of people's opinion on this matter, Mr Eastman has had his day in court, and the jury has reached a decision."
"One of the strengths of our system is politicians avoiding commentary on individual cases, a protocol I respect and will follow in this case."