"Sub-human". An appropriate phrase for political discourse?

It appears that Nick Bourne AM, Tory leader in Wales, has got into a spot of bother for a piece of splen vented against the BNP. Describing them, on his blog in February as, "nasty, mean, distasteful and grubby bunch of sub-human flotsam and jetsam".
His comments are being considered by the Welsh assembly's standard's committee. 180 complaints were made, no doubt almost entirely by BNP members.

The BNP, is a pretty vile party, the worst combination of vicious xenophobia and socialism to be found in the British Isles, barring only Sinn Fein. However the words "sub-human" are probematic in the extreme.

After all this concept of dehumanising political opponents is normaly the tactic of facsists and communists, not so called liberal parties. But looking at what else he says about them and how they should be treated I think he is about right.

Beat them with arguements, not with the legal process. (That said using the words of Henrich Himmler to attack them is perhaps no the most sensible thing to do).

Another thing, he boast about being over in Brussels last week talking to Commission officials and others about "Higher Education". Isn't education supposed to be a National issue?