Until Steny Hoyer's reelection in 2007, Fallon held the position's longevity record.

[1] Growing up, Fallon attended public schools, Calvert Business College, and Johns Hopkins University.

He engaged in the advertising sign business and made his entry into politics by becoming chairman of the Democratic state central committee of Baltimore, Maryland, in 1938.

Fallon was also one of the congressmen wounded during the 1954 United States Capitol shooting.

[6][7] Fallon was an unsuccessful candidate for renomination in 1970 to the Ninety-second Congress after being labeled by conservationists as one of the dirty dozen for his record as the twelfth most anti-environmental congressman at that time.