Former Canadian prime minister Pierre Trudeau left an impressive record of progressive social reforms when he retired from politics in 1984. But he left some unfinished work, including reforming Canada's cannabis laws.

His son Justin Trudeau - who will become prime minister today - is now poised to complete that work with his promise to legalize the recreational use of cannabis.

In 1969, Prime Minister Pierre Trudeau tasked a royal commission with examining the basis for Canada's pot prohibition. The Le Dain Commission of Inquiry into the Non-Medical Use of Drugs - named after chairman Gerald Le Dain - would spend 55 months researching cannabis before making its final report.

During that time, U.S. President Richard Nixon put America further than ever from repealing cannabis prohibition by initiating the War on Drugs, which is still being waged today. But in Canada, it appeared as though the drug war might soon be over, and that possibility made international onlookers take a keen interest.

"This is the opportunity for Canada to lead the world," said John Lennon on Dec. 22, 1969, as part of his testimonial for Le Dain commissioners.

Lennon praised Canada for being the only country in the world committed to researching drugs, as opposed to maintaining criminalization based on scant scientific evidence. You can read the former Beatle's full testimonial here.

Two days later, the Lennon and Yoko Ono met Trudeau in Ottawa:

thestar.com

In 1972, the Le Dain Commission reported that Canada's penalties for cannabis were "grossly excessive." Their recommendations included repealing the prohibition on personal possession, and tasking law enforcers with preventing adolescents from using cannabis.

The Trudeau government did not act on the recommendations, however, and millions of Canadians continued being punished for marijuana-related offences.

And now Justin Trudeau becomes prime minister, more than 40 years after his father dashed the hopes of people counting on reform. In the words of Lennon, it's another opportunity for Canada to be a world-leader - to finish the work his father began.

h/t Toronto Star, Toronto Sun, NORML Canada, CBC