Tommy Chong, best known as one half of the comedy duo Cheech and Chong, celebrated his 80th birthday this year and admits to W5 to smoking weed regularly.

For most of his adult life, cannabis has been illegal, yet Chong has continued to smoke it openly and publicly.

The actor who is known for playing an endearing, hippie stoner is an opinionated activist for cannabis reform. In Chongs’s mind, weed has never been illegal, “so I never even give it any thought,” he says.

With Canada on the cusp of legalization, Chong’s life work as the “Grandfather of Pot” is almost done.

He was born on May 24, 1938 in Edmonton, Alberta, to a hard-working Chinese immigrant father and Scottish-Irish mother.

Chong spent the first few years of his life on what he calls “a manger, which was a converted chicken coop.” Growing up under-privileged in Alberta in the '40s as a Chinese-Caucasian child was not easy. Chong says he was constantly teased and tormented by his peers because he was different.

In high school, he gravitated to the African American community where he fell in love with jazz and blues music. It was at the age of 17 when he smoked his first joint. Chong remembers it well. He tells W5, “that changed my life. I smoked a little bit of the joint, got high, listened to Ornette Coleman, Lonely Woman for the first time, I remember it so well. And then, then about a week later, I ended up quitting school and I became a blues musician.”

In the early 1960s, Chong moved to Vancouver where he ended up playing in a Motown band called “Bobby Taylor and the Vancouvers.” Chong continued to smoke marijuana even though local authorities were cracking down on drug use and arresting people en masse who broke the law.

Chong managed to avoid arrest and kept smoking because, to him, weed was more than a psychedelic drug. He believed in the drug’s healing powers. He says he found cannabis helped him creatively with his music.

It was in Vancouver where Chong met his future comedy partner Cheech Marin, but it was not laughs that brought them together, it was music. Chong and Cheech started a band but soon realized that it was their opening dialogue that drew the crowd’s cheers, not their music.

So, the pair changed their act to a comedy routine in the late '60s and began performing at a Vancouver strip club called the “Shanghai Junk.” Their brand of comedy was considered counter-culture by many experts, as the pair focused mainly on drug use and the effects of weed on people’s behavior.

Over the next few years, their popularity continued to grow and in 1971 the comedy duo recorded their first album, “Cheech and Chong." It peaked at number 28 on the Billboard 200. Their follow-up album “Big Bambu” was an even bigger success, making it to the number two spot on the Billboard Charts and earned the pair a Grammy for Best Comedy Recording in 1974.

They reached the biggest audience yet in 1978 with the release of their first feature Hollywood film, “Up in Smoke” — a movie that many credit with establishing the ‘stoner’ comedy genre.

It has been 40 years since “Up in Smoke” was released and Chong has maintained his advocacy for pot. He even claims cannabis has helped him beat cancer twice, though he admits he does not know how. “Yeah, right now I’m cancer free,” Chong tells W5. “I don’t know what it does, I think it affects the immune system.”

Now, with cannabis legal in many parts of the U.S., Chong has gone into business with his son Paris selling branded marijuana products called “Chong’s Choice” in the United States.

As the laws in Canada are being drafted to decriminalize cannabis, Chong has these words for the Canadian government: “Now if they're smart and Canada’s smart, they will keep the taxes within reason.”

Recreational cannabis use is set to become legal in Canada in the summer of 2018.

'Pot Pioneer' airs Saturday night on CTV, or above in our video player or official W5 YouTube channel after the show airs