He found work with the Inland Revenue, and became a supporter of the Labour Party.
[1] In 1927, Prichard wished to stand for the London County Council, but he was refused permission by his employer.
From 1949, he led the joint standing committee of the London boroughs.
In 1950, the government decided to permit its employees to sit on London County Council, and Prichard was elected as an alderman, and by 1955/56 was the council's chair.
He left the council in 1967, but was re-elected to it in 1970, representing Wandsworth.