An MMA judge failed to inform an athletic commission about a potential conflict of interest with a fighter and his training camp -- and signed his name to the fact he had carried no such conflict in pre-fight paperwork, MMAFighting.com has learned.

Doug Crosby, a longtime MMA judge, has a long-standing feud with coach Ray Longo and his team, according to Longo and police documentation obtained by MMAFighting.com. One of Longo's fighters, Al Iaquinta, competed at UFC Fight Night: Mendes vs. Lamas on April 4 in Fairfax, Va., and Crosby was assigned to judge his co-main event fight.

Not only did Crosby apparently fail to disclose the potential bias to the Virginia Boxing and Wrestling commission, he signed a document that stated he would notify someone from the commission if he had a conflict of interest. MMAFighting.com was able to obtain the paperwork, which is public record, through the Virginia Department of Professional & Occupational Regulation.

The document reads: "I will notify the Executive Director, Event Inspector, or Assistant Event Inspector prior to the beginning of the above event should there be a conflict of interest with any Fighter(s), Bout(s), Training Facilities, Cornermen, Fighter(s), Manager(s) or Promoter(s)." Crosby signed his name on the bottom.

Virginia DPOR spokesperson Mary Broz-Vaughan also told MMAFighting.com that Crosby is not a usual Virginia judge, but he was assigned to the event by the UFC. A UFC official clarified that it is common practice for the UFC to provide a list of out-of-state officials and referees to athletic commissions if needed, but ultimately the decision on who to use falls with the specific commissions.

Crosby scored the fight 30-27 for Masvidal. The other two judges, Dave Tirelli and Cardo Urso, both had it 29-28 for Iaquinta, giving Iaquinta a split decision win. Most media members had the fight 29-28 Masvidal, according to MMADecisions.com. Crosby gave the third to Masvidal, though most others had it for Iaquinta.

John McCarthy, the pioneer of MMA refereeing and judging, said the scores don't matter; what matters is whether the perception of a bias is present.

"I don't know what Doug did," McCarthy told MMAFighting.com. "But he should have at least advised the commission. That's the right thing to do. It ain't about you. It ain't about me. If there's any chance that could be a problem, don't put the problem out there. So you don't do a fight, so what?"

As further evidence of a potential conflict of interest, Longo also said he received an insulting letter from Crosby at his LAW MMA facility in December 2013. Longo said surveillance footage showed that the letter was dropped off by a man Crosby refers to as his nephew. It also was not the first time Crosby had sent a derogatory correspondence, Longo said.

An investigation was undertaken by the Garden City (N.Y.) Police Department at that time and it was found that Crosby had sent "numerous letters and cards" to Longo at his gym and his residence, according to a police report obtained by MMAFighting.com.

The police report states that Crosby was contacted by officer Carlo Fracassa and advised to stop contacting Longo. Crosby said he would not have any further contact and all further calls from police could be directed to his attorney, per the report.

Longo also claims that a female gym staff member obtained a court order of protection against Crosby, which remained in place for three years. MMAFighting.com was unable to confirm or disprove such a document, because family court records in New York State are sealed to the public.

Crosby denied Longo's claims on Chael Sonnen's "You're Welcome" podcast last week. Sonnen stated on the show that Longo brought the alleged letter by Crosby to the Nevada Athletic Commission to prevent Crosby from judging a fight between Anderson Silva and Longo's fighter Chris Weidman. Longo denies doing that. Crosby said he never sent a letter in the first place.

"I've never written Ray Longo a letter and I don't have any nephews, so I'm not sure -- unless I call my brother and he tells me he has a phantom son, I'm not really sure how to address that," Crosby said. "All I can tell you is I don't have any nephews and if I did have a nephew I would be playing golf with him right now. And I never wrote him anything, so if he presented something to a state agency claiming that I wrote it and then created a phantom nephew that delivered it to him, then I would venture to guess that my attorney is gonna to have to discuss that with the athletic commission at some point in the near future."

Longo, who coaches the Serra-Longo fight team alongside Matt Serra, said he wishes no ill will toward Crosby. He just doesn't believe Crosby, who also works as a stunt coordinator in the film industry, should be judging fights involving his athletes or competitors he does business with.

According to his IMDB page, Crosby is an accomplished stunt coordinator who was worked on such films as 12 Monkeys, Black Swan and I Am Legend. Crosby said on Sonnen's show that he has been helping MMA fighters get stunt roles in movies and television for close to 20 years. Longo questions whether that is a conflict of interest with regards to judging.

"I think with the judges there should be some disclosure as to who they're affiliated with and who they're not," Longo said. "It's hard enough to judge a fight with no attachments to anybody.

"If Derek Jeter is eating lunch with the umpire, do you want that guy calling balls and strikes against you?"

Iaquinta told Ariel Helwani on The MMA Hour earlier this month that Crosby asked him to take part in a project through an intermediary and Iaquinta turned it down. Crosby denied that on Sonnen's podcast last week.

"I never offered him a role," Crosby said. "I never offered him anything."

However, Steve Koepfer, an MMA trainer in New York, told MMAFighting.com that he was the one who offered Iaquinta and one of his own students roles on behalf of Crosby. Koepfer said it was a small stunt part in one episode of a television show and Iaquinta turned it down because of Crosby's feud with Longo.

Interview requests from multiple members of the MMAFighting.com staff were evaded by Crosby over the past month. MMAFighting.com has been attempting to interview Crosby for more than a year, but he will not go on the record.

Crosby has also come under the microscope most famously for two other questionable scorecards. He gave all five rounds to Frankie Edgar in the first fight between Edgar and B.J. Penn in 2010 and also had inconsistent scores of 10-8 and 10-10 in the first fight between Robbie Lawler and Johny Hendricks at UFC 171 in March 2014. After Edgar-Penn I, Crosby went on the Underground online forum to defend himself and troll users.

Crosby, who has a solid judging record overall, was defiant in his original appearance on Sonnen's podcast two weeks ago. As to whether he thought he should have judged the Iaquinta-Masvidal fight, Crosby stated: "That question should be answered by the individual who assigned me to that fight. Not by me. I'm not an administrator."

He then added: "If I didn't think I should have been assigned to it, I wouldn't have sat down."

But McCarthy, who helped write the unified rules of MMA, said that in order to preserve the "integrity of the sport," any potential biases must be told to the commission before the fight.

"If there is something, even if it's perceived, [the judge] should always bring it up as a point to the commission," McCarthy said. "Look at it, deal with it -- so there's no doubt."

There is plenty of precedent for recusing yourself. McCarthy said he just saw it during a boxing/MMA hybrid show a few weeks ago with a referee in a main event fight. California State Athletic Commission executive officer Andy Foster told MMAFighting.com that judge Wade Vierra recused himself from a Nate Diaz fight in 2013, because the two have trained together before.

There are warnings about conflicts of interest in the regulations of each state's athletic regulatory bodies, Foster said. Broz-Vaughan said if Crosby did indeed lie on the document it might not have been a "specific regulatory violation."

But it does raise many questions, regardless of how Crosby scored the Iaquinta-Masvidal fight. Just the perception of a bias can taint the judge's credibility, according to McCarthy.

"It's weird when you now look at it in hindsight," McCarthy said. "When there could be absolutely nothing out of the question, he scored it that way, but that's when people start to bring in, 'Oh, he doesn't like Longo and Serra.' Perception becomes reality. It doesn't have to be real."

Crosby, though, thinks that letting outside forces remove judges from bouts opens up a can of worms.

"I think it points to a bigger problem, and the bigger problem is, if you put yourself as an athletic commission and you put yourself in a disadvantageous position and you allow any cornerman or whatever to automatically request that a judge be recused because you've got a beef with them," he said. "Ray's a fine example. If you're going to recuse everyone that Ray Longo's got a beef with, Ray's got more beef than the Chicago stockyard. It would be basically Ray judging the fights by himself because I've been places where he's got a beef with every judge and every cornerman and everyone in the stands and the guy selling popcorn and the valet.

"The situation you run into is if an athletic commission is automatically going to entertain the notion of recusing judges because of a cornerman waving a piece of paper that might be from a Chinese restaurant for all we know, delivered by a phantom, then you're giving cornermen the power to decide who judges fights."