In prison , bank robber Alvin Karpis had taught him to play the steel guitar . Now , living mostly by panhandling , he soon got to know Mary Brunner , a 23-year-old graduate of the University of Wisconsin -- Madison .
While in prison , a bank robber taught him to play the steel guitar.p137 Living mostly by panhandling , he soon met Mary Brunner , a 23-year-old graduate of the University of Wisconsin -- Madison .