A motorcycle club known for its inclusion of law enforcement officers had been involved in several high-profile fights with rivals across the country before Saturday’s deadly brawl in Denver.

Experts and a lawyer for the Iron Order Motorcycle Club say culture clashes with “outlaw” groups — also known as 1 percenters — led to violence in recent years.

The confrontations even rose to the attention of federal agents, who in a 2014 report noted the club’s rapid expansion despite bloodshed.

“Probably the best way to put it in a nutshell is to say the Iron Order has been having problems with everybody,” said Steve Cook, executive director of the Midwest Outlaw Motorcycle Gang Investigators Association.

Authorities on Monday identified the 46-year-old man killed in the Colorado Motorcycle Expo fight.

Several guns have been recovered, but no arrests have been made. Seven men were injured in the fight; three remain in critical condition.

Representatives from the Iron Order and Mongols Motorcycle Club blame each other for the clash.

Denver police Cmdr. Ron Saunier said the battle started as an argument at the bottom of a stairwell and quickly escalated. Investigators are still unsure what the fight was about.

During the expo, various motorcycle clubs had established territory within the National Western Complex, Saunier said. He didn’t know if the territories were sanctioned or had been claimed once members showed up.

Four people were shot, including Victor Mendoza, who died of a single gunshot wound. An attorney for the Mongols said he was a member of the club.

The Mongols released a photograph they say was taken moments before the fatal shooting and showing an Iron Order member holding a handgun at the top of a stairwell. Mongols members, including Mendoza, are looking on as the armed man is led away.

Later, he was taken off in handcuffs by police but not arrested.

The Iron Order calls itself a law-abiding club, setting itself apart from others linked to criminal activity. That proclamation has been questioned.

Arthur Musselman, a teacher at the Georgia Public Safety Training Center who specializes in motorcycle gangs, said some Iron Order members have been implicated in crime. Still, they are not considered on the same playing field as outlaws.

“They have not been classified in the same ranks as your traditional 1 percent motorcycle gangs,” Musselman said.

John C. Whitfield, a lawyer for Iron Order, said the group is despised by counterparts. Their three-piece patch, their law enforcement membership and their club colors are points of contention.

“When you start wearing patches like the three-piece patch, even if you wear a certain color, it can make some of these 1 percent clubs unhappy,” Whitfield said. “Because of that we are always getting poked and tweaked. It has led to some altercations.”

Typically, new groups are expected to ask permission from outlaws before using certain insignias. Whitfield says the Iron Order has not followed that unwritten rule.

The Bureau of Alcohol, Tobacco, Firearms and Explosives said in a 2014 report that the Iron Order’s patch “has infuriated” members of several outlaw groups, including the Hells Angels, Iron Horsemen, Pagans and Bandidos. Back-and-forth beatings ensued.

In 2014, an Iron Order recruit shot and killed a member of the Black Piston Motorcycle Club in an altercation outside a Jacksonville Beach, Fla., restaurant.

Last year, the Iron Order was linked to a Mississippi shooting with bikers tied to the Bandidos Motorcycle Club.

The Iron Order’s lawyer said those shootings were in self-defense and the Denver brawl was no different. Outlaw groups see it differently.

Donald Charles Davis, known as “The Aging Rebel” for his motorcycle club musings on his namesake blog, said the Iron Order “very much are troublemakers.”

Davis, who has been a member of several clubs, said the Iron Order has picked fights throughout the country. In a posting after the Denver shooting, he said the group is widely despised “not only for its members’ aggressive rudeness … but because it is widely considered to be a ‘cop club.’ “

“Just about any 1 percenter club you can name has had violent confrontations with the Iron Order Motorcycle Club,” Davis said. “They just don’t play by the rules.”

Stephen Stubbs, an attorney for the Mongols Motorcycle Club, on Monday reiterated claims the Iron Order was responsible.

“It was a fair fight until the Iron Order member pulled out a gun, Stubbs said. “For them to come out and play the victim when they picked the fight is outrageous. They are a bunch of cops who say the rules of society don’t apply to them.”

The Iron Order says a Colorado Department of Corrections officer fired a shot during the expo brawl, and the DOC confirmed Monday evening that employee Derrick Duran was involved.

Authorities have not said whether the officer’s shot hit anyone.

Duran is on administrative leave with pay while the case is under investigation, according to the DOC statement. He has been with the department since May 2012.

Attempts to reach Duran were unsuccessful.

Police say they don’t know of other law enforcement officers who were involved.

Jesse Paul: 303-954-1733, jpaul@denverpost.com or @JesseAPaul

Iron order

Founded in 2004 by a former federal agent, the Iron Order has been rapidly spreading across the nation. It’s known for having a base of police and corrections officers as well as active-duty military and government contractors, but also claims members from all walks of life.

Mongols

The Mongols Motorcycle Club is an international group classified by the U.S. Department of Justice as a highly organized criminal enterprise.