Tendentious:
marked by a tendency in favor of a particular point of view : biased [Merriam-Webster]
Sounds like a synonym for partisan to me. Noted on Lawfare:
The political strategy here is laid out candidly in this generally tendentious essay yesterday by Andrew Klavan, entitled “Obama Spied, Media Lied,” which makes clear the ambition to change the subject from Russia’s intervention to one of the political misuse of the intelligence apparatus.
