In an ideal government, everyone would have complete and utter freedom of their opinions, but unfortunately, nowadays plenty of politicians in every party are more than willing to sell out for personal gain or to fulfill their goals. It seems like we've lost the generation of politics where everyone thought of the greater good for all regardless of party affiliation.
There's not much isle crossing anymore and it's almost a bad thing to let an opposing party pass good legislation because it may take away from your popularity.