The defence lawyer in the trial surrounding an alleged terror plot to behead the prime minister has declined to call any witnesses.

Lawyer Mitchell Chernovsky told a Brampton court on Wednesday that he believes the evidence already presented will be enough to clear his client, a 20-year-old who was one of 18 people arrested in 2006 in relation to the alleged plot.

The Crown claims the scheme included plans to blow up buildings and storm Parliament Hill.

Much of the evidence has suggested the accused did not know about the plot and joined the group to learn more about Islam, his newfound religion. He cannot be named because he was 17 years old at the time.

The charges against several members of the group have since been dropped but ten men still await trial, including the group's alleged leader. Video and audio surveillance footage entered as evidence indicate the ringleader kept lower-level members of the group in the dark about his plans.

The arrests came after an investigation by CSIS and the RCMP that involved wiretaps and videos of the accused on two camping trips, one in northern Ontario and another near Guelph.

In a surprising turn of events, Crown prosecutor John Neander turned on his witnesses twice during the trial, attacking them for inconsistencies in their testimonies.

Closing arguments are expected to be held next week. It could take Justice John Sproat weeks or months to come to a verdict.