Report co-author Abby Deshman said Canadians spend more than $850 million on pretrial detention even though most of those arrested are facing non-violent and minor charges.
"There is a presumption of innocence that we base our justice system on," she said. "We don't think it's being reflected in our bail courts."
The study, entitled "Set Up to Fail: Bail and the Revolving Door of Pretrial Detention," found the use of pretrial custody has risen nearly 300 per cent over the last three decades. During the same time, crime rates have declined, with 2012 recorded as the safest year since 1972.
On an average day in 2012-13, more than 25,000 people were incarcerated in provincial and territorial jails. Of those, about 55 per cent were awaiting trial or bail hearing — a higher number than convicted and sentenced offenders.
The personal, societal and financial costs associated with pretrial custody are "overwhelming," Deshman said.
"They are generally given no warning that they are being put in pretrial detention," she said, adding this can result in loss of income, housing problems and a need for emergency child care among other things.
"Even a short stay in detention without warning can be incredibly disruptive."
The report found it costs about $170 a day to keep someone in pretrial detention, compared to $5 per day to supervise someone in the community.
Manitoba had the most people in pretrial detention, with 66 per cent of its jail population waiting for trial or bail hearing.
Corey Shefman, with the Manitoba Association for Rights and Liberties, said the province is setting people up to fail because of its zero-tolerance policy for breaches of bail conditions. Someone can be returned to jail for being five minutes late for an appointment, he said.
While Manitoba tops the list for pretrial detention, Ontario, Yukon and Alberta also have high rates, with about 60 per cent of people in jail awaiting trial or bail hearing.
Prince Edward Island had the lowest ratio, with 18 per cent of its jailed population in pretrial detention.
Bail conditions are even more difficult for alcoholics or drug addicts, Deshman said. In Ontario, she said, it's common for people with addictions to be released provided they abstain from alcohol or drugs, but are given no support.
The use of sureties in Ontario is another issue.
Sureties are usually friends or family members who pledge money to act as "jailers" in the community, said Deshman, who called the practice "onerous." In addition, accused are often required to move in with a surety — which may not always be practical.
In contrast, British Columbia processes the majority of bail cases without sureties, she said.
Report co-author Nicole Myers, who spent about 200 days observing bail courts in Ontario, said the use of sureties is slowing the bail process because it takes time to find the right person.
"More than half of the cases are told they have to come back another day," she said.
Myers said pretrial detention should be used for a small number of violent or dangerous offenders.
"We're seeing a shifting of the punishment to a pre-conviction state," she said.
Deshman said Ontario's overuse of sureties is especially harsh for remote aboriginal communities.
People often have to be flown out of their community and can spend a significant amount of time in jail waiting for transport.
The report includes recommendations such as a moratorium on imposing abstention conditions during bail, reducing the use of sureties in Ontario, and ending Manitoba's zero-tolerance policy for breaches of bail conditions.