More than 140,000 court appearances have been delayed because of the pandemic since March 2020.
Officials say extra money and resourcing is going towards improving court scheduling.
But the number of criminal cases is increasing, leaving those inside the justice system frustrated.
Independent victims' advocate Ruth Money said for complainants in court cases, increasing delays were hitting their ability to work or even function at home.
"People literally put their lives on hold. The trauma involved in waiting for a trial or waiting for a sentencing, or even a bail hearing - it distracts you.
"Trauma isn't linear. It means you can't function often like 'normal people' do."
Since the pandemic began, Ministry of Justice figures show 144,000 court appearances have been delayed or rescheduled because of Covid.
That is out of 2.4 million appearances, such as sentencings, bail applications and pre-trial hearings.
The rate has slowed rapidly since last year - in May 2022 there had been 142,000 delays - but in its place has come an 8 percent increase in active criminal cases for the year to 38,926 in May. In May 2022, there were 35,920.
Money said helping victims navigate the system was made harder by the sense of delayed justice.
"You can explain that this is normal. You can explain some resilience methods that they can employ.
"With these delays being so long as they are, they're harmful. There's no other way to describe them."
The time taken for a criminal case to conclude, such as through a plea or verdict, highlights this.
According to written parliamentary questions answered by courts minister Rino Tirikatene, in May criminal cases were taking 176 days to go through the system.
This was up from 134 days in May 2020 and 114 in May 2018.
Criminal Bar Association president Chris Wilkinson-Smith said this was causing problems as cases backed up.
"It's a perennial problem, even if you put the Covid blip to one side.
"We're supposed to have trials without undue delay which, I think, should mean really between that from the time you make your first appearance there should be a trial within a year."
That is generally not happening - with jury trials in Auckland in particular taking longer to begin after the city's extended lockdowns, according to the ministry.
Wilkinson-Smith said that risked innocent people staying on remand in prison, at a cost of $400 a day.
"What we've become used to is delays of sometimes two or three years, or even longer, for a trial to be heard. That's become so ingrained."
Delays were corrosive for everyone, and the association would like to see a deadline for holding trials introduced into law or judges' practice, he said.
"What it really needs is some sort of leadership to take hold of the issue and say, 'Look, these delays are too long.'
"We shouldn't just say, 'That's the way it is.' We should say an undue delay is longer than a year and fix that, say, fix a target that has to be met."
Money worries that would mean defendants who were guilty might not face trial.
She has ideas to speed the system up, too.
"We need to look into longer sitting times, whether that be an hour each day, whether that be night court, whether that be Saturday mornings.
"We need to break the back of these terrible backlogs."
"The trial itself is an emotional thing and there needs to be a bit of distance, but it does tend to be taking longer.
"Criminal law's a tough game and I think there's only a certain number of criminal lawyers who can do these big cases, and they have to have time to prepare."
The system was under pressure and needed to be examined to make sure it was operating as it should.
"I think we probably do need to do more measures about what's a system that works fairly, appropriately and justly, and also efficiently.
"It's an awful thing to wait for these cases, on all sides."
In a statement, chief operating officer Carl Crafar said industrial action by court staff and Cyclone Gabrielle were partly behind the increase in active criminal cases.
Officials and judges worked closely during the pandemic to keep courts going, for example by using audio-visual links, he said.
And $90 million in government funding was behind "additional judicial resources and proactive resourcing and scheduling work with the judiciary, legal profession, court registries and scheduling teams is ongoing to ensure cases are progressed".
Crafar said jury trials were suspended for "several months at various times" since March 2020, due to Covid restrictions. But they were going again under the later Covid-19 protection framework from December 2021 to September 2022.
"Throughout Covid-19 courts have adapted the way they operate to enable more court events to be completed and cases to be resolved.
"For example, during the alert level 4 settings in 2020 only 32 per cent of the normal number of court events in the district court were able to be completed, while during the Covid-19 protection framework settings 95 per cent of the normal number were being completed."
