NPCs flag yellow now, you cannot provoke (or entice if it were in the game), attack or harm them any more.
I do remember way back when though. Funniest thing I recall was being in a mage shop trying to buy some regs. I was in a hurry (who wasn't, it was a competition to buy regs) and ended up buying a stack of purple potions on accident. I tried to drop them out of my pack, but lagged just at that moment and ended up double clicking. The explosion went off in my pack, damaging the nearby Mage shop employee, and a split second later my screen showed a guard putting me down for attacking an NPC. Ahh, good times.