As a delegate to the Democratic National Convention of 1924, in New York, he proposed inserting an anti-Klan plank into the party platform, despite the presence of an estimated 300 Klansmen in the hall.

The attempt caused the "hissing and booing of Klansmen along with fist fights, chair tossing, and destruction of convention decorations".

Opposed by William Jennings Bryan and other party leaders, the plank was voted down, and with it the potential presidential candidacy of Catholic Al Smith.

This is exemplified in his volume "Meddybemps Letters" that included a "Hall of Fame" with bitterly satiric biographies of the leading Republicans of the time.

Pattangall was appointed Associate Justice of the Maine Supreme Judicial Court (by the Republican administration) in 1926, but only broke with his party over President Franklin Roosevelt's New Deal, to which he became bitterly opposed.