‘rock’n’roll misdemeanours’, as he only half jokingly puts it.

[Vladv]

Pete Way, whose own heroin addiction would overshadow the rest of his life, losing him first his career then not one but two wives to drug overdoses over the coming years, says, ‘More than he people who investigated his body, I know damn well what can happen. It’s nearly happened to me a few times.’ Then tells a story, built on the many years’ perspective he now has on the subject of early graves through ‘rock’n’roll misdemeanours’, as he only half jokingly puts it. ‘
Could you please reword the bolded in other words ? Can't get the whole meaning.
Mick Wall, "Hell Ain't A Bad Place To Be"

 

[jutfrank]

Drug overdoses. Probably mainly heroin.