RangerWickett said:
"A paladin must be of lawful good alignment and loses all class abilities if she ever willingly commits an evil act. Additionally, a paladin's code requires that she respect legitimate authority, act with honor (not lying, not cheating, not using poison, and so forth), help those in need (provided they do not use the help for evil or chaotic ends), and punish those who threaten innocents."
Let's examine that statement.
"A paladin must be of lawful good alignment and loses all class abilities if she ever willingly commits an evil act."
I'd say "evil acts" includes using torture to gain information, killing prisoners (unless there has been a legetimate trial that condemns them to death for some offense outside the realms of warfare), and so on. No surprises there.
"Additionally, a paladin's code requires that she respect legitimate authority,"
That means respecting their commanding officer in these circumstances. Which can be hard when that guy is an evil bastard of a general. Whether or not it is possible to remove such people from the "legetimate authority" category depends on the legal, ethical and cultural context, and thus is highly game world dependent. Still, obeying the direct orders of a superior is something that should
never be done lightly, and a paladin will need to realize what fighting as part of an army will need for him. If he finds himself in a situation where he can't follow such orders because they violate his ethics, he must face the consequences - which usually means explaining his actions before a military tribunal, and accept its rulings, up to and including execution.
Because of these reasons, paladins will probably be reluctant to serve under anyone who isn't another paladin, or else known for being very honorable. In many cases, paladin-led units will be under a seperate chain of command from the "regular" army...
"act with honor"
This means "obeying the accepted rules of warfare", such as they exist in this setting. This
can mean obeying the rules of chivalry, if such exist in the setting for the warrior class, but does not
have to. The middle ages didn't have fireballs or huge monsters as part of large-scale warfare, and it is likely that combat docrines will be different under these circumstances.
With chivalry, the assumption was that
all noble warriors would fight like this. If this isn't the case, then it is unlikely that these rules would apply to paladins only.
Examples from the modern-day rules of war that might apply here include neither attacking nor hiding in hospitals or religious buildings, no fighting under "false colors" (the uniforms of an enemy), and no fighting without a uniform or other insignia that mark you as a soldier. If such rules exist in the setting as well, then a paladin has to adhere to them even if his enemy don't.
"(not lying"
Where does this restriction come from? Well, people must be absolutely certain that they can take a paladin at his word. If a paladin tells you something, you
must be able to trust his word as you trust the rock on which your feet rest.
However, this does not prevent the paladin from misdirecting the enemy as long as such misdirection does not violate the rules of warfare. A possible example is sending out messages to other units that contain fake orders in plain text, and the true orders encoded into the message. If the enemies intercept the message and jump to the wrong conclusions about the order, then that's their problem - the paladin wasn't addressing this message to
them, after all. The same goes for concealing troop movements or making units appear larger than they are - all of these are simply clever use of warfare. Only when he gives his actual
word to someone is it different. If he tells an enemy commander: "We will cease the battle for the night to retrieve the dead bodies if you do likewise", then he
must adhere to it.
"not cheating,"
Again, this means "adhering to the rules of warfare". "Cheating" is when someone breaks the rules - whether it is at a game or at war. A paladin can still play poker and bluff his way to victory as long as he does not
lie. And a paladin can still use deception and misdirection as long as these are accepted parts of warfare (which does not need to be the case if the chivalric code is prevalent - see above). That includes hiding and attacking from ambush, if that's what it takes.
not using poison, and so forth)
In warfare, this can apply to "poisoning the well" and similar tactics - like using disease. I'd also extend it to "scorched Earth tactics" that destroy the land in order to deny resources to the enemy. Creating long-term suffering for the land and its people to win against a foe probably qualifies as an evil deed.
"help those in need (provided they do not use the help for evil or chaotic ends),"
If enemies have surrendered and the paladins have them in their power, he should treat them well and give them food and water. Not neccessarily more than to his own troops, but he shouldn't let them starve or even kill them.
and punish those who threaten innocents."
The paladin must make sure that his own forces understand exactly what is and what is not acceptable in warfare - especially concerning civilians, which count as "innocents" for the purpose of warfare. And he also will make special efforts to punish those enemy troops who purposely harm civilians, if at all possible.
Anyway, these are my two cents on the issue.