Lawbringer

Lawbringer is a perk in Fallout 3.

Description
You will get a note from The Regulators telling you that they "require your aid in bringing the scum and pestilence that inhabit our home to justice" and ask you to report to Sonora Cruz at Regulator HQ for details. Sonora Cruz, the leader of the Regulators, will pay the Lone Wanderer for each "evil" person brought to justice (killed) and requests their finger as proof. She will pay 5 caps per finger unless the Wanderer has 750 or more Karma, at which point they will pay 10 caps per finger, this is determined by your Karma before the turn-in, not after. Each finger will give the Lone Wanderer 10 Karma, regardless of their current Karma. If you are 10 Karma away from 750 and you have multiple fingers, dropping all but one and doing 2x turn-ins will net more caps.

Bugs

 * Sonora Cruz can’t take more than 999 fingers at a time. If you have more than that in your inventory when delivering, she only takes 999 but still rewards you for all of the fingers (12,800 caps for 1,280 fingers with very good Karma, for instance). You can deliver the remaining fingers for more Karma and caps.
 * It is possible that Sonora Cruz will run away from the Regulator HQ and will not return. Fast traveling to the HQ often spawns various combination of hostile creatures and/or robots. They are normally busy killing the brahmin outside the HQ, however they engage you upon your arrival. If you enter the Regulator HQ before killing the hostiles, all of the Regulators, including Sonora Cruz will flee from the area and not return. She can usually be found outside, or can be brought back to the HQ by using the console. Once the hostile creatures are killed, she will usually talk to the Lone Wanderer again, but sometimes must be disabled, then re-enabled to reset her scripts, or she will be continuously fleeing. It should be noted that if you kill whatever is outside before you enter the Regulator HQ Sonora Cruz will not flee.
 * Even with the Lawbringer perk, Regulators in the HQ will hold a bounty notice saying that you're a dangerous person who is to be shot on sight for a reward of 1000 caps when having an Evil or Very Evil Karma status. This does not effect the behavior of the residents of the Regulator HQ, only the Regulators sent to bring you in.