The decision in the Keith Jardine vs. Gegard Mousasi fight at "Strikeforce: Diaz vs. Daley" was considered controversial by some, and subsequently placed on the examination table and analyzed according to the unified rules.
Debates over how to score the bout ensued: effective striking versus effective grappling, which deserved the highest priority, the worth of Jardine's takedowns, and how the point deduction for Mousasi's illegal up-kick factored in. However, the unified rules are merely a general baseline under the umbrella of the Association of Boxing Commissions for scoring MMA bouts. This means that they serve as a foundation upon which each state builds its own individual rules, so the specific regulations of the hosting state are what governs each event.
For example, New Jersey's official rules are unique in that they feature a "sliding scale" to prioritize effective striking and effective grappling based on the amount of round-time that occurs in each category. From: http://www.nj.gov/oag/sacb/docs/martial.html
(k) Judges shall use a sliding scale and recognize the length of time the fighters are either standing or on the ground, as follows:
1. If the mixed martial artists spent a majority of a round on the canvas, then:
i. Effective grappling is weighed first; and
ii. Effective striking is then weighed
2. If the mixed martial artists spent a majority of a round standing, then:
1. Effective striking is weighed first; and
2. Effective grappling is then weighed
3. If a round ends with a relatively even amount of standing and canvas fighting, striking and grappling are weighed equally.
In Nevada, as recently discussed with Keith Kizer, more detailed descriptions are provided to explain how referee stand ups and submissions are treated. Additionally, it was reported in September of 2010 that California was undergoing a trial with monitors for the judges. Therefore, the rules and regulations of MMA can vary from state to state (and often do), so it was the California State Athletic Commission's rules in particular that presided over the "Strikeforce: Diaz vs. Daley" event.
On California's Department of Consumer Affairs website, their State Athletic "Code of Regulations" describes how to score an MMA bout under Article 3, Section 520.
§ 520. Method Of Judging
Referees and judges shall score all contests and determine the winner through the use of the ten-point must system. In this system, the winner of each round receives ten points and the opponent a proportionately less number. If the round is even, each fighter receives ten points. No fraction of points may be given.
At the termination of the contest or the termination of each round, as determined by the commission's representative present at the event, the cards of the judges shall be picked up by the referee and delivered to the commission representative assigned to check the totals. The majority opinion shall be conclusive and if there is no majority then the decision shall be a draw. When the commission representative has completed verifying the score, the ring announcer shall be informed of the decision and shall announce the decision.
Since this obviously does not mirror the wording of the unified rules, I contacted California State Athletic Commission Executive Director George Dodd for clarification.
"We use the Ten Point Must system just for scoring the round. When determining the winner of the round the judges would default to the unified rules," Dodd said. "But, the California rules do not give a clear description or does not prioritize the scoring criteria for MMA."
Dodd continued to explain that the traditional scoring elements found within the unified rules are taken into account to determine the round winner, but they are assessed as a whole rather than by a detailed description with a rigid hierarchy.
"You can't say striking or grappling is the number one thing," Dodd explained, "because it depends on how the round plays out. Damage caused, striking, grappling, control and aggression are all taken into account, but California's rules aren't geared towards specific and prioritized descriptions."
"The fact is," he concluded, "that if Mousasi would not have fouled Jardine -- which it was a clear foul -- he would have won the fight."