LAS VEGAS — MMA's Unified Rules are on the brink.

On Tuesday here, the Association of Boxing Commissions (ABC) will vote on multiple proposed rules, including major alterations like revised scoring criteria and an updated definition of a grounded fighter. There is a strong chance the body will approve some, if not all of the changes.

However, some commissions present at the 28th annual conference will vote against these new rules and not adopt them in their respective states even if passed. Other state commissions have not sent any representatives here and are pursuing the development of a rival organization to the ABC.

The result could be a frustrating one for fighters and fans — a situation where the sport's Unified Rules are fractured and important regulations change state to state.

The New Jersey State Athletic Control Board (NJSACB), which has deputy commissioner Rhonda Uttley-Herring in attendance, is not in favor of the proposed new definition of a grounded fighter or the elimination of heel kicks to the kidney as a foul, NJSACB counsel Nick Lembo told MMA Fighting in a phone interview Monday.

If the ABC body votes to approve those changes, the NJSACB will not follow through and adopt them in its state, which is its right. The ABC does not have authoritative power over state commissions, but merely makes recommendations and gives guidelines.

The proposed definition of a grounded fighter sets out to eliminate what officials have dubbed "playing the game," when fighters lean down and place a finger tip on the ground to avoid kicks or knees to the head. The current rule states that any part of the body other than the feet touching the ground means a fighter is grounded. The revised rule says that, too, but makes it so that if it's a hand touching the ground it has to be both hands and either the palms or fists.

Lembo said that is a major concern for New Jersey, because it puts fighters in a situation where they can take knees and kicks to the head and face in a position where it is difficult to defend themselves.

"I am not in favor of anything that increases head strikes, especially in light of the NFL concussion lawsuits and what we're learning now about head injuries," Lembo said.

Instead of a rule change, Lembo proposes that referees make it clearer to fighters during rules meetings prior to events that "playing the game" will be illegal and not establish a fighter as being grounded.

New Jersey is also not in favor of removing the foul for heel kicks to the kidneys, for medical reasons. It's rarely seen in MMA, though Lembo said any strikes to the kidneys are illegal in boxing. Lembo doesn't think it's prevalent enough as a maneuver to warrant altering the Unified Rules. He also doesn't like the use of the word "damage" in the new proposed scoring criteria.

Damage has always been an insinuation in the scoring rules, but never actually written because of the raw verbiage. Lembo, as a lawyer thinking of legal implications, would still prefer to use the words "impact" or "effect" rather than damage, though he is not against the spirit of the revised scoring criteria.

The MMA rules and regulations committee wants the word damage in the scoring criteria for clarity, which the current language lacks in places. Longtime official John McCarthy has long been a proponent of "damage" and uses the word when training judges. Lembo admits he has used it, too, but would prefer not to see it as part of the written rules, because it's already implied and obvious.

"[NJSACB commissioner] Larry Hazzard has said, ‘If I have to tell my judges that they need to take damage into account for scoring, then I have the wrong judges,'" Lembo said.

New Jersey will not adopt the proposed grounded fighter definition if it is passed by the ABC and it's unclear if the commissions that have not sent representatives — like Missouri and Ohio — will implement any potential rules changes in their states.

Leaders from Missouri and Ohio have started the Association of Combative Sports Commissions (ACSC) as a counter to the ABC. Officials from those states had previously held leadership roles in the ABC, including former ABC president Tim Lueckenhoff, the executive director of the Missouri Office of Athletics.

The ACSC held its conference earlier this month in New Orleans. Influential states like New Jersey, Illinois and Oklahoma all sent representatives. Illinois and Oklahoma have reps at the ABC this week as well. Lembo said New Jersey wishes to be neutral, which is why it sent reps to both conferences.

"The ACSC came to being in an effort to move in a new direction in working to protect the health, safety and welfare of combative sports contestants," a press release sent out by Lueckenhoff in in February stated. "Linking athletic commissions worldwide that are involved in the regulation of combative sports, the ACSC will stress the importance of transparency, accountability, strategic planning and open communication in all of its endeavors."

The division could lead to plenty of confusion among fighters and fans, especially if rules and regulations are different in ACSC states compared to ABC states.

"The whole reason you go through this process with the ABC is so you get everybody to be on that same page, that same sheet of music," McCarthy said. "Because you don't want one commission doing it one way and then you go to another state the next week and you're doing something different. The fans need to understand what the rules are. They need to understand the way the rules are enforced. It's good for the fans. It's good for the officials. It's good for the fighters. The fighters should not be trying to change what they're doing from week to week, depending on where they're going to be fighting. The NFL doesn't change their rules when they go from San Francisco to New York. It's the same no matter what. That's exactly what we need in MMA."

For this reason, Lembo was not happy that a host of commissions like California, Nevada, Mohegan Sun and Kansas have begun doing early weigh-ins for MMA events. Commissions in Pennsylvania and Ohio have different ideas about weigh-in procedures and there hasn't been a vote on anything standardized in the ABC. Missouri has also used an early weigh-in for Bellator and Invicta events, as have other commissions after requests by the UFC.

Lembo is also a fan of uniformity and would like to see the ABC come back together, which is why he questions changes like the definition of a grounded fighter and if they're so important that they are worth creating further division.

"Are these changes so necessary?" Lembo said. "Is there such an outcry and need for these changes that it's worth most likely destroying the Unified Rules? And then we're back to telling fans and fighters, ‘The fight is in New Jersey, you can't do this' or ‘Your fight is in Alabama, you can't do this.' The sport should be bigger than us. Why not check it out with everybody first? Let us all be together before we start breaking things down."

Mike Mazzulli, the president of the ABC and the Mohegan Sun commission director, said Missouri and Ohio are still members of the ABC and have paid their dues, but are now considered inactive. He defended the recommended changes by the ABC rules and regulations and medical committees, saying they did an "excellent" job, pointing to standardizing apparel for women's MMA and the proposal of a foul to reduce eye pokes, both of which New Jersey supports. The rules and regulations committee includes the likes of MMA legends Randy Couture and Matt Hughes.

"The ABC is in the best interest of the fighters," Mazzulli said. "We're here to protect them and we're here to move forward. The Unified Rules of MMA and the rules of boxing were written many, many years ago and we're in the process of making sure we update them on a yearly basis."

Despite the absence of some commissions, Mazzulli said this year's ABC Conference is 60 percent larger than any of its predecessors and new international commissions in Brazil and Mexico are being welcomed. More than 300 people were in Las Vegas this weekend doing training for certification classes to become ABC judges, referees or other officials, he said.

"You see a diverse community here and we're all friends and we want to look out for the best interests of the fighters," Mazzulli said. "The individuals that formed that other organization, if that's what they're trying to do, then good for them. But we are the prominent organization when it comes to the regulation of combative sports and we're going to move forward with or without the other guys."