My companion's character sheet has a light/dark side rating, though it is at 0.
Is there a way for them to become more good/bad by making, or forcing them to make, alignment choices?
Or is this a bug in the UI and should be removed? Bioware already removed the Social/Valor bars and replaced them with Affection bars, so I assume it was left there on purpose. But I haven't seen anything that suggests companion alignments can be changed from what is already in their Codex entry stating their likes/dislikes.
Best Answer
They don't have a rating, and they're always shown as neutral. I'm pretty sure their rating scales only show up because it is a part of the character sheet that they don't have something else to display there, although they could be adding it to later versions of the game as well. There was some original talk of the kind of crew missions you sent them on affecting the rating but that obviously hasn't/won't be implemented. (Diplomacy missions only affect your own rating.)
Note however that your companions are limited by your alignment. They can't use items that don't match your character's alignment.