Pinkerton security guard who shot and killed Navy veteran, 49, at 'Patriot Muster' protest in Denver will be charged with murder, DA announces

An unlicensed Pinkerton security guard accused of fatally shooting a pro-police protester following opposing rallies will be charged with second-degree murder, Denver's District Attorney Beth McCann has announced.

The charge will be filed against Matthew Dolloff, 30, on Monday - the deadline for prosecutors to bring charges - in the death of Lee Keltner, 49, McCann said in a statement released on Thursday. 

She did not elaborate on her decision to prosecute Dolloff, who was protecting a KUSA-TV producer at the time, for second-degree murder, rather than the first-degree murder charge he was arrested on suspicion of after the shooting on October 10.

People convicted of second-degree murder face a mandatory sentence of between 16 and 48 years in prison.

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Pinkerton security guard Matthew Dolloff, 30 , on Monday will be charged with second-degree murder for the killing of Lee Keltner, 49  

In this October 10 photo, Dolloff, a TV station security guard, right, turns after fatally shooting Keltner following opposing rallies

Dolloff has been held without bond in the Denver County jail since his arrest, jail records show. No attorney was listed for Dolloff.

A lawyer for the Dolloff family said he acted in self-defense, local media reported this week. 

Police say Keltner, a US Navy veteran, was in a verbal dispute with a 27-year-old man as the rallies broke up last Saturday when Dolloff and a 25-year-old person got into an altercation with Keltner.

Investigators said a 60-year-old man stepped in between Keltner and the 27-year-old man to urge them to stop before Dolloff and the 25-year-old person - believed to be a producer - engaged in an altercation with Keltner. 

In the KUSA video, the 27-year-old counter-protester, who was wearing a 'Black Guns Matter' shirt, is heard telling Keltner: 'Shoot me mothaf***a. F***ing kill me then n***a.' 

The 60-year-old man then steps in and pushes the counter-protester back as he says: 'Don't f***ing touch me n***a. Don't f***ing touch me.' 

The counter-protester looks directly at Keltner says: 'F***ing mace me,' as Keltner walks toward him holding a can of mace.  

This image captures the moment Keltner sprays mace, left, as Dolloff, right, fatally fires a semiautomatic gun at him in Denver

Dolloff drops his gun and kneels with his hands in the air as he is taken into custody after the fatal shooting. He could face up to 48 years if convicted of second-degree murder

WHO ARE THE 'PATRIOT MUSTER' PROTESTERS?

Patriot Muster is the name given to pro-police activists who have attended rallies organized by John Tiegen, an ex-Marine and Blackwater private security guard. 

The group was formed over the summer as Denver, along with dozens of other cities across the US, was roiled by protests against racism and police brutality. 

Patriot Muster made headlines in July when it hosted a 'Back the Blue' rally that descended into chaos when protesters began clashing with counter-protesters. Tiegen accused the counter-protesters of throwing soup cans at his followers. 

Tiegen organized another Patriot Muster rally on Saturday at the Denver Civic Center, under the slogan: 'Stand up, show up.'

The slogan bore similarities to President Donald Trump's response when asked to condemn white supremacists and the Proud Boys. Instead of disavowing them he said: 'Stand back and stand by.' 

Black Lives Matter protesters led by the Denver Communists responded by creating their own rally in the same location, dubbed the 'BLM-Antifa Soup Drive'. 

The 'soup rally' was meant to be ironic in response to Tiegen accusing leftist protesters of throwing cans. 

Tiegen foreshadowed violence at the event on Friday, telling KNUS: 'I'm not going in there to do violence, but I'm going to be prepared to do violence.'

Keltner then looks directly into the camera before walking toward the producer and saying: 'This is not the place for a camera. F*** you. Get the cameras out of here or I'm going to f*** you up.' 

Keltner appears to push the producer, knocking him backward as he engages in a physical fight with Dolloff.

Dolloff steps back and a hissing sound, likely from Keltner deploying mace, is heard before the video cuts off.  

Dolloff fired his semiautomatic a split-second later, according to another video taken by a man who had been live-streaming the argument between Keltner and the 27-year-old counter-protester.  

The cell phone video taken by KUSA's producer suggests that Keltner was upset that his dispute with the first man was being recorded by cameras.

It shows Keltner in a confrontation with a man wearing a T-shirt that read, 'Black Guns Matter.' A bystander is trying to defuse the argument, which occurred after a 'Patriot Muster' demonstration and 'BLM-Antifa Soup Drive' counterprotest downtown.

The video then shows Keltner, holding a spray can, walking out of view. A man's voice - it´s unclear if it´s Keltner - is heard saying the area was no place for cameras.

'Get the cameras out of here or I'm going to f*** you up,' the unidentified man says. Keltner and Dolloff are then shown scuffling before the video stops.

The producer resumes filming after the shooting and tells arriving police that he is with the press and says of the man who was shot, 'That guy was going to get me.' He also says the security guard shot Keltner because Keltner used mace.

Someone out of view can also be heard saying 'he's got magazines in his coat' but it is not clear who the person is talking about.

Keltner's son told the Denver Post his father was not affiliated with any group, but was at the rally to support police. 

In a Facebook post over the weekend, the victim's mother Carol Keltner claimed that her son was shot 'because he backed police' and said: 'The Left has gone too far.' 

Dolloff was hired through the Pinkerton agency to provide security for a crew from KUSA-TV, an NBC News affiliate, the station said in a statement, adding it requested that security personnel be unarmed. 

Keltner was a US Navy veteran. At the time of his death, he was taking part in a pro-police 'Patriot Muster' rally 

Pinkerton said on Twitter that Dolloff was not an employee 'but rather a contractor agent from a long standing industry vendor.' 

Earlier this week Denver's Department of Excise and Licensing confirmed that Dolloff did not have and has never had the license needed to serve as a private security guard.  

KUSA-TV has said it did not know that he was unlicensed. 

Pinkerton: The security firm that contracted Patriot Muster shooter   

Pinkerton was thrust into the spotlight after it was revealed that 9News used the security firm to hire Matthew Dolloff. 

The firm was founded as Pinkerton National Detective Agency in Chicago in 1850 by Scotsman Allan Pinkerton.

At the height of its power in the early 20th century, Pinkerton was the largest law enforcement agency in the country. 

The US Department of Justice contracted out investigative work to Pinkerton in the 1870s, before the Anti-Pinkerton Act of 1893 banned the government from employing individuals affiliated with the firm. 

Pinkerton gained a reputation for intimidating factory workers while helping companies keep unionists out of their operations. 

Today, the word Pinkerton is still associated with union conflicts - but the firm focuses efforts on threat intelligence, risk management and executive protection.

The company was purchased by Swedish security company Securitas AB in 1999. It's headquarters is now located in Ann Arbor, Michigan.