Keith Harding, former membership secretary of the Paedophile Information Exchange (Pie) was made Worshipful Master of the Mercurius Lodge in Cheltenham, Gloucestershire, in 2011.
The child molester, who died last summer, presided over ceremonies and rituals from an ornate throne.
Harding was convicted of an indecent assault against four children aged eight and nine in 1958 and classified a Schedule-1 offender, which meant the offence remained on his criminal record all his life.
His name was also on a list of about 400 Pie members seized by police in 1984, the year the organisation disbanded.
The Sunday Express revealed earlier this month how Harding met MPs Cyril Smith and Leon Brittan in the 1980s when he ran a north London antiques store.