Co-starred on The Wire (2002) with another actor named Thomas J. McCarthy. Both actors were credited as Tom McCarthy, but they are not related.
Graduated from Boston College in 1988.
Graduated from New Providence High School in New Providence, NJ.
Directed 3 actors to an Oscar nominated performance: Richard Jenkins, Mark Ruffalo, and Rachel McAdams.
As of 2016, has appeared in two films that were nominated for the Best Picture Oscar: Good Night, and Good Luck. (2005) and Michael Clayton (2007), and in addition to that, he wrote two films that were nominated for the same category: Up (2009) and Spotlight (2015), the latter film in which he also directed.
He is of Irish descent.