Question: Don Barry Mason was the founder of the Psychedelic Shamanistic Institute (PSI), which other member that's Welsh, that died on 10 April 2016?
Sentence (from "Howard Marks"): He was eventually convicted by the American Drug Enforcement Administration and handed a 25-year sentence to be served at Terre Haute; he was released in April 1995 after serving seven years.
Relevant evidence: No