I can remember when Liberals were usually strong advocates of free speech. It would be a good thing if that type of Liberal were to regain control from the outright loonies.
You're thinking perhaps of the "Classic Liberal", which is to say, (small-l) libertarian. Freedom of speech is a central libertarian principle.
http://en.wikipedia.org/wiki/Classic_liberal
"Modern Liberal" is nearly a synonym for "Socialist", and socialists are not noted for supporting free speech.