Cathy Evelyn Smith, the Canadian singer who injected John Belushi with a fatal speedball, has died.

On the night of March 4, 1982, John Belushi was partying hard at the Chateau Marmont. A few people, including Robin Williams and Robert DeNiro, dropped in. So did Cathy Evelyn Smith, a former backup singer from Hamilton who was known to sell drugs to the Rolling Stones. At some point in the evening, she shot up Belushi with a speedball. It was a fatal overdose of coke and heroin. He was found dead and alone by his fitness trainer and bodyguard around noon the next day.

No one suspected Smith until she gave an interview to the National Enquirer two months later in which she admitted to administering the speedball. The case was reopening, she was extradited from Ontario, and charged with first-degree murder. That was reduced to involuntary manslaughter for which she served 15 months in jail. When she was paroled, she moved back to Toronto where he worked as a legal secretary. She also often lectured to teenagers about the perils of doing drugs. (One other note: In 1991, she was arrested in Vancouver with two grams of smack in her purse.)

Now Smith herself has died at the age of 73. She’d been in poor health for the last couple of years.

Two musical items about Smith. First, she claimed to be the inspiration behind “The Weight,” the hit from The Band. She certainly did party a lot with the band and turned down a couple proposals from the group’s Richard Manuel.

Second, she worked as Gordon Lightfoot’s employee for a time in the 70s. That gig evolved into her becoming his mistress, a situation that led to Lightfoot going through what was then the most expensive divorce in Canadian history. She was definitely the inspiration for Lightfoot’s 1974 hit, “Sundown.”