He was a Labor Party member of the New South Wales Legislative Assembly from 1930 until 1932, representing the electorate of Randwick.
He was reinstated in March 1919, but resigned two months later to become state secretary of the Amalgamated Coachmakers' Association, a role he held until his election to parliament.
[1] Flanagan was the Labor candidate for Randwick at the 1927 state election, but was defeated by Nationalist Ernest Tresidder.
His political career was to be short-lived, however; Labor's popularity collapsed as Lang was dismissed by the state Governor for his controversial response to the Great Depression, and Flanagan lost his seat to United Australia Party candidate Arthur Moverly, one of many Labor MLAs to lose his seat that year.
[3] He died on 3 March 1949(1949-03-03) (aged 60) from a cerebral abscess at St Vincent's Hospital, Sydney and was buried at the Congregational Cemetery at Randwick.