Adjective
tendentious (comparative more tendentious, superlative most tendentious)

  • (of persons or their words) Having a tendency, written or spoken, with a partisan, biased or prejudiced purpose, especially a controversial one; implicitly or explicitly slanted; biased.

That he was a supporter of the cause was clear, because his reports from the front were tendentious.

https://en.wiktionary.org/wiki/tendentious