Yes, POLITICAL is a Scrabble word!

Letter values in Scrabble US: P 3, O 1, L 1, I 1, T 1, I 1, C 3, A 1, L 1.

Is it a valid word?

POLITICAL is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

involving or characteristic of politics or parties or politicians
of or relating to your views about social relationships involving authority or power
of or relating to the profession of governing