Most of the charges laid after police raids on Toronto marijuana dispensaries last year won't be proceeded with.

The Public Prosecution Service of Canada has either withdrawn or won't proceed with charges against 45 of the 90 people arrested.

It also won't proceed with charges against another 27 people who agreed to enter into peace bonds that impose restrictions on them.

A total of 186 charges were laid after a day of city-wide police raids in May 2016.

Toronto Police spokesman Mark Pugash says the resources required to prosecute all 90 people was a factor in prosecutors' decision to not go ahead with most of the charges.

Despite the fact that dozens of individuals who were charged won't go to court, Pugash said that police still achieved what they set out to do, taking a bite out of the local drug scene.

"What we've seen is money taken off the streets, drugs taken off the streets, a reduction in the number of dispensaries, and those are all important markers in preserving public safety," said Pugash, who added that going to court is just one of the options that police consider.

Police say that large amounts of cash, property and drugs were also surrendered by most of the individuals with stayed charges, and that peace bonds will further restrict individuals from being involved in pot shops.

Paul Lewin, a Toronto lawyer who was involved in some of the cases, said he thinks many of the charges were dropped because the prosecutors sensed that the charges didn't warrant criminal resources. He said that "the writing was on the wall" that many of the charges would not go ahead.

He said it shows the raids were a waste of time and a poor use of scarce judicial and police resources.

"It was a very stressful experience for the young people involved, because trafficking is a very serious offence that people frequently go to jail for," said Lewin.

"It really leaves everyone in a state of uncertainty that the criminal law is process is periodically used against people who sell medical marijuana, even though recreational marijuana is going to be legal soon."

The federal Liberal government has said it intends to legalize recreational marijuana by July 2018.

However, Pugash said that Toronto police plan to continue riding illegal pot shops in Toronto.

"What we've seen as a result of the activity is there are significantly fewer dispensaries in Toronto than there were 16 or 17 months ago," said Pugash.