So there are no fallen paladins in D&D?Paladins & Evil Clerics: This makes no sense. What I think you're failing to realize is that, unlike real-world religions, D&D isn't about evil as someone being good but overcome by temptation. In D&D evil is not just someone's sins building up, or a series of choices.
Alignment as some cosmic force doesn't really fly in Eberron, IMO. Or in any game that I've ever played in. Evil characters are evil because they're willing to hurt others to get what they want. They generally don't (cultists excluded) choose to align themselves with "cosmic evil."
All of those methods can be fooled, even the Holy Avenger. Detect spells can be fooled. Zone of truth and discern lies can be fooled. Every magic trump card can be trumped itself, or is simply unreliable (i.e. anything that allows a saving throw).A Paladin's ability to sense evil is meant to detect creatures of evil and slay them. Paladins are evil-killing machines. To doubt a paladin, a real paladin who you can presumably test as a paladin (lay on hands, alignment spells of your own, get them to hold and use a Holy Avenger sword, etc.), isn't the same thing as doubting a polygraph. You might as well doubt a magnet for finding iron!
But more than that, being "evil" is not in itself grounds for execution in a civil society. There are all kinds of compromises that are necessary to wield power, and the authorities may not appreciate when some zealot kills one of their political allies. Or kills one of their wealthy benefactors. Or slays the head of the local criminal underworld, who had cooperated with the authorities to keep crime at an acceptable level. Or murders a respected businessman, with no proof of any actual wrongdoing. And that's assuming that the people at the top are not evil themselves... It's fine to say, "I'm a paladin! The gods speak through me, and that person deserved to be cut down in cold blood," but it's not necessarily going to save you from the dungeon or a noose for pissing off the wrong people.
100% agreement here.As a side note, I am glad most of the alignment nonsense is gone from 4e.