Dawes claims he was originally the leader of a gang in the Hub back in California. However, he was apprehended and sentenced to imprisonment in the correctional facility in the Mojave Wasteland for starting a riot. Dawes will grant access to the NCR Correctional Facility to a character who has sufficient reputation with the Powder Gangers in exchange for 100 caps. Alternatively, assisting Joe Cobb in Run Goodsprings Run will earn free access to the facility.
Wearing faction armor to overcome low reputation with the Powder Gangers is ineffective with Dawes, as he will note that he doesn't recognize the wearer as somebody with whom he served time and will still demand the entrance fee of 100 caps. After the fee is paid, Dawes will see through the faction disguise and attack. Killing Dawes at this point will not make the others hostile unless it also triggers a reputation drop to vilified.
With no more than a modest Sneak skill, it is possible to achieve Hidden status beside or behind Dawes and pickpocket his NCRCF visitor's center key (a much easier skill check than for any of Dawes' other possessions). There is no Karma loss for this, nor for using the key on the door.
He will greet a female character more nicely than a male character.
"That's us. We got sent here to fix the rails and make some new ones, and for that we got to use dynamite. Of course, dynamite works pretty good against caravan guards, too. So, that's what we do - rob and blow things up."