Actually, it’s pretty common for scum to stick out their necks “defending” someone who is town. If they are successful, they’ve got someone who feels they are “on their side”. If they aren’t, they can pat themselves on the back later on and tell everyone “I told you so!”
I specifically disagree with anyone who defends anyone else. It shows knowledge that the average townie simply cannot have. There’s also the point that you’re attacking a whole gaggle of people on supposedly spurious reasoning. Scum can coordinate, so they would (I imagine) build better arguments, not weaker ones.