Split off from this post which talks about how to run Dogs under d20 in response to players' fear of other systems.

I suppose the first point is that if players don't want to play non-d20 games, then don't play them! But I'm going to ignore that and suggest that it is possible to use the d20 system to play Dogs.

The basic d20 roll is d20+ranks+stat bonus+other bonuses against a difficulty class (DC).

Conflicts in Dogs go through 4 stages:
talking
physical but not fighting
fighting
gun fights

The d20 equivalent I see as:
Persuasion (bluff, intimidate, diplomacy)
Skills
Non-lethal combat
Lethal combat

d20 operates a hit-point system for combat damage (lethal and non-lethal), a success/failure system for skills and two systems for persuasion, an attitude system for diplomacy which changes someones general demeanour towards PCs and a success/fail system for bluff and intimidate.

Dogs uses the number of dice left as a representation of how much more a character can influence the conflict. As can be seen from the above, the d20 situation is less simple. d20 also does not have the wide range of traits that Dogs has but I think this can be got round by using the skill ranks instead.

I propose the following system for d20.

When a PC starts a conflict, they have a pool equal to the skill ranks of the skills that they use in the conflict, this represents their Conflict HPs (CHPs). As new skills are brought to bear, the pool will grow. If the conflict escalates to violence HPs are added to the pool (or optionally are used instead).

You might give extra CHPs for certain feats such as leadership or background details, although you might like to keep these to a minimum and probably mark them on character sheets as they are acquired rather than arguing them out when a conflict arises.

So for example, Bother Jed starts a conflict with Sister Eve over the placement for a new barn. Jed might use his Diplomacy (1 rank) and Craft (Building) (6 ranks) to give him an initial pool of 7. Sister Eve uses Intimidate (6 ranks) and her Leadership feat for 3 more ranks giving her a pool of 9.

Players make the usual d20 rolls on skills. So Jed rolls Diplomacy with the usual DC of Eve's attitude and Eve rolls intimidate with the DC based on Jed's Level and Wisdom. A success depletes your opponent's pool, by 1 pt per 3 points success, and a failure depletes your own at a similar rate.

If you go 0 or negative CHPs you must give or escalate (you do either earlier if you like).

So Jed quickly loses CHPs and his player escalates to skills and rolls his Craft (Building) skill, explaining that Jed is drawing a site plan to show how his placement for the barn makes more sense. And so on.

Finally, Jed gets annoyed and lashes out at Eve. He's a pretty strong fighter than she is and quickly starts to get on top. Will Eve give or will she stab him?

The big issue, of course, is not about what system you use for this, but whether players will understand and abide by the fact that their PC will be in some circumstances persuaded of things that the player doesn't want. It's this more than anything that is the difference between Dogs and d20.

Very insightful.  This bears considering.  I like the idea of taking the D20 system and pushing it in some of the directions that games like Dogs go.

A lot of the problems of persuasion that you mention can be handled with skillful application of stakes.  There has to be something that each side can WIN.

Another good game to borrow from in this instance would be TSOY, especially when it comes to the way it handles damage.