[8][9] After earning his master's degree, Grim worked as a legislative analyst for the Marijuana Policy Project.

[12] Grim left his position at HuffPost in 2017 after nine years with the paper, joining The Intercept to head its Washington, D.C.

[10] According to Politico, while at The Intercept, Grim focused the media organization's policy interests towards people who are "progressive welfare state enthusiasts, anti-interventionists and surveillance paranoids".

[12] In August 2020, Grim used emails from the University of Massachusetts Amherst chapter of the College Democrats to dismantle an attempt to smear progressive candidate Alex Morse.

[15] In July 2024, Grim and Jeremy Scahill, the co-founder of The Intercept, founded Drop Site News.

[18][19] In 2016, Grim published a blog post in which he questioned FiveThirtyEight's models and predictions for the 2016 United States presidential election.