More than 50 protests against controversial Bill C-51 took place across Canada and in Windsor on Saturday.
Organizers say demonstrations will take place in dozens of cities in Canada, from Victoria to Halifax, in an event they have dubbed "Defend our Freedom."
The Conservative government introduced the legislation, known as Bill C-51, in January and says it will make Canadians safer.
The wide-ranging bill would give police much broader powers and allow them to detain terror suspects and give new powers to Canada's spy agency.
Critics say the bill, if enacted as law, will infringe upon Canadians' civil liberties and right to privacy, especially online.
"I'm really worried about democracy, this country is going in a really bad direction, (Prime Minister Stephen) Harper's taking it in a really bad direction," said protester Stuart Basden.
"Freedom to speak out against the government is probably at jeopardy ... Even if you're just posting stuff online you could be targeted, so it's a really terrifying bill."