Sept. 18 might be a day that Willie Nelson would just as soon forget. It was on that date in 2006 that the singer was arrested for possession of marijuana and narcotic mushrooms while on the road in Louisiana.

The incident began with a commercial vehicle inspection of Nelson's tour bus: “When the door was opened and the trooper began to speak to the driver, he smelled the strong odor of marijuana,” law enforcement said in a statement about the arrest. A subsequent search produced 1 1/2 lbs. of marijuana and more than 3 oz. of narcotic mushrooms. The large quantity of drugs was enough to charge Nelson with a felony of distribution, but since four other people on the bus, including Nelson's sister Bobbie, also claimed to own the drugs, they were each charged with a misdemeanor.

Nelson, who is an outspoken advocate of the legalization of marijuana, was also arrested in 2010, in Texas, when 6 oz. of marijuana were found on his tour bus. But the 86-year-old is hopeful that the drug will soon be legal all across the country.

"I think it's only a matter of time," he tells the Huffington Post. "The economy going off is going to help it a lot. There's money there, and anyone with any brains at all can say, 'Why do you want the criminals to make all the money off of this when it's proven that it won't kill you unless you let a bale of it fall on you?'"

Nelson's advocacy for the legalization of marijuana has even extended into his music: He included a song titled "Roll Me Up and Smoke Me When I Die" on his 2012 album, Heroes. In 2015, the country legend launched his own line of marijuana and related products, called Willie's Reserve.

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