He now campaigns for the legalisation of his favourite smokeable substance and is currently performing live shows around the UK.
TNT caught up with Marks to get the dirt on his days as dope smuggler.
What was the most exciting moment of your drug smuggling career?
I suppose that’s when I got acquitted of bringing in 15 tons of marijuana in1981. I’d obviously been guilty, so that was an exciting moment.
How did you pull that off?
I reckon the defence lied to the jury. The usual way!
And what was the most frightening moment?
Probably when I first went into the federal penitentiary where I stayed for several years. That was frightening.
Any particularly scary experiences in there?
There was just so much violence all the time. I was always witnessing fights, violence, gang rapes. Just witnessing a horrible stage of life.
So how did you manage to protect yourself?
From gang rape? I had a potbelly and no one fancied me.
Yikes. And from the violence in general?
Being a foreigner, I was lucky as I didn’t have to have any allegiances with a particular gang so that made a difference.
You famously had 43 aliases. What was your favourite disguise?
A full-on beard and ‘tache was probably the most comfortable. I never had any plastic surgery but I once disguised myself as a woman. I didn’t wear a dress – I wore a very long fur coat over some jeans actually. But I did wear a wig.
Didn’t you find smoking so much weed hindered your abilities?
Everyone is different. Smoking makes quite a number of people better at whatever they like doing, but it also makes people worse at what they don’t like doing doing. It’s actually a very good way of determining, whether you want to do something.
You did some serious travelling as a smuggler. What was the most interesting place you went to?
The strangest would have been Nepal. It’s a vastly different culture and was like going back into the Middle Ages. Of course, it’s a very important country in the world, where all the Hindu Gods were born and where Shiva keeps on smoking.
If you could only ever have smoked one joint in your life, which would it have been?
It would have been back to the first joint I smoked in Mustang, Nepal, in 1976. It was very, very strong, very Himalayan. Everything I looked at was either funny or yellow. There wasn’t anything I looked at that didn’t fall into one of those two categories.
Is drug tourism a legitimate reason to visit a country?
Absolutely! Brazil, and most South American countries, has the greatest variety of psychotic drugs as well as weed and pot.
What would you say to people who worry you make a dangerous lifestyle glamorous?
Well I’m just trying to be a good role model to geriatrics!
Do you think that cannabis will ever be legalised?
I think progress in that direction is extremely slow. It’s only been illegal for a hundred years or so, which is just a hiccup really. It’s been a disastrous social experiment in my opinion.
How much do you smoke these days?
About 20 joints a day.
Secretly, do you ever get paranoid or whitie when you smoke too much?
I usually crawl between the sheets before that happens.
You studied philosophy at Oxford, what’s your philosophy of life?
Don’t take yourself too seriously. I think that would be it.