“Mortals with an evil alignment, however, are different from [evil outsiders]. In fact, having an evil alignment alone does not make one a super-villain or even require one to be thwarted or killed. The extent of a character’s evil alignment might be a lesser evil, like selfishness, greed, or extreme vanity.”
Good: “protect innocent life”
Evil: “debase or destroy innocent life”
“Innocent” here means without proof of committing a capital crime (a crime punishable by death by good authorities). Many good individuals and deities argue that there are no such things as capital crimes, as all killing is evil, and put up many practical hurdles to prevent accidental killings in retribution. Capital crimes generally include first degree murder (intentionally killing sentient creatures), treason, perjury leading to the death of an innocent, kidnapping resulting in death, or creating undead. To some authorities, crimes such as aggravated rape, drug trafficking, arson or sexual abuse of a minor might be considered capital crimes. In most cases, a series of individuals must all agree that the perpetrator is guilty of the capital crime before a punishment of death may be considered permissible.
Being good does not require legal authority. The above are examples of what laws a good ruler or deity might enact. The actual laws of a society need not be good, though almost all good and neutral societies consider murder to be an least a serious crime, and generally a capital crime. Evil deities and individuals might provide a death penalty for having a holy symbol of a good deity. In this case, having the holy symbol would not be an evil act, and most good characters would see anyone enforcing this law as evil.
Killing a sentient creature because the laws of its society are evil (e.g., a goblin) is itself an evil act. And in many jurisdictions of good law, it would be a capital offense. And most good folk don’t take kindly to people who talk about their killing others.
An example Lawful Neutral creed:
1) Worship the Lawful Neutral god
2) Don’t worship anything else even to indirectly worship the Lawful Neutral god
3) Respect the name of the Lawful Neutral god
4) Don’t force your slaves to work more than 6 days in a row
5) Respect your elders
6) Don’t kill sentient creatures
7) Only have sex with who the church authorizes
8) Don’t steal
9) Don’t lie
10) Don’t covet other people’s things