Martin Dwaine Johnson told authorities that an associate and an accomplice were planning to kill Sen. Barack Obama using a sniper rifle simply because he is black, but the threat was not deemed credible by federal authorities.

Colorado’s U.S. Attorney Troy Eid said today the threats did not meet the legal standard to charge the men with making a threat against Obama.

“There is a difference between a true threat and the reported racist rantings of drug abusers,” Eid said during a press conference.

But Eid did announce his office had filed federal gun and drug charges against Tharin Gartrell, Shawn Adolf and Johnson

“(Shawn) Adolf said that he wanted to kill Obama on the day of his inauguration and additionally stated that Adolf said he would specifically use a 22-250 sniper rifle and high powered scope, and find high ground to set up and shoot Obama,” according to a federal criminal complaint filed today.

The documents say Johnson said Gartrell came to Denver with Adolf specifically to kill Obama.

Gartrell and Johnson were charged with possession of a firearm and possession of body armour by felons and possession of methamphatamine with intent to sell, according to court records.

Johnson was also charged with alleged possession of a firearm by an offender and possession of methamphetamine with intent to sell.

Eid insisted that the men posed “no credible threat” to Obama or visitors to the Democratic National Convention.

“This involved a gang of meth-heads who were all impaired at the time,” Eid said.

Johnson made an initial appearance on related state drug charges this morning in Denver court and waived the reading of the charges against him. He is being held on $10,000 bail.

The case began 1:37 a.m. Sunday when Gartrell, 28, who was driving a rented Dodge pickup, was pulled over in Aurora after he was seen swerving and driving erratically. He was driving without a license and was on probation for a methamphetamine conviction, authorities learned.

Police then saw a wig and two high-powered rifles in the truck, along with a hunting scope, a bulletproof vest, a walkie-talkie, several boxes of ammunition and methamphetamine. One rifle was threaded for a silencer attachment. The other, which was stolen from the Sherman County Sheriff’s Office in Goodland, Ka. in 2005, according to court records released today.

Three backpacks contained equipment for making methampahetamines: three large boxes of matches, two glass cooking vessels, pseudo-ephedrine pills and a bottle of pH base. Officers found a baggie of suspected methamphetamine in Gartrell’s pocket.

Gartrell told authorities the weapons belonged to his cousin Adolf, according to federal documents.

Police went to the Denver Tech Center Hyatt Hotel, 7800 E. Tufts St. and contacted Johnson, 32, and a girl. He told police that Adolf was at a sixth floor room at Cherry Creek Hotel in Glendale.

At 6:37 a.m. Sunday, police knocked on Adolf’s hotel room door. Adolf told officers to wait while his wife changed her clothes.

Officers then heard “glass breaking inside the room and an unknown female screaming.”

Adolf, 33, had jumped from the sixth-floor window, landed on an awning four floors down and then jumped to the ground, breaking his ankle, Glendale Police Chief Victor Ross said.

An unnamed female witness from Fort Morgan, who had been driven to Denver on Saturday with Adolf, told Colorado State Patrol officers about possible threats against Obama, according to the federal court records.

The witness said in the Hyatt hotel room, Adolf and Gartrell talked “negatively” about Obama using racial epithets. She believed they were “white supremacists.”

They “could not believe how close he was to becoming president,” and that no black should live in the White House.

In a subsequent interview between CSP troopers and Johnson, the suspect said he was with Adolf and two women at the Hyatt at 10 p.m. Saturday when one of them started talking about killing Obama with a camera with a gun hidden in the lens. But Adolf and Gartrell dismissed her statements.

Johnson cried and said Adolf and Gartrell talked about going hunting, but what they meant was that they were going to kill Obama during his speech Thursday.

“There were no political reasons for wanting to kill Obama, and that the only reason to kill Obama is because Obama is black,” the court record says.

Adolf is being held in lieu of $1 million bail on numerous warrants from across Colorado, Aurora police Lt. Bob Stef said.

One of the warrants is out of Texas on a felony charge of tampering with government records, according to CBI records. He also is being held on a Weld County warrant for burglary, vehicular theft, theft; an Adams County warrant for larceny; a Jefferson County warrant for a drug case; and a Kit Carson County warrant for three theft counts. In addition, he is wanted out of Kit Carson County on a separate warrant for failure to appear on a felony charge, according to CBI records.

Adolf has an extensive criminal record. He was sentenced to eight years in prison in 1997 for drug and illegal-weapons charges. He also served sentences for assault, forgery and numerous theft charges.

Gartrell is being held on $50,000 bail on amphetamine possession and on an Arapahoe County arrest warrant, according to CBI records. He was convicted of drug-possession charge in 2005 and was arrested for a drug charge in May 2007.

According to court records, he had been living at a friend’s house for the past three months while unemployed. For five years, he was self-employed disc jockey. He recently lost his job as a cook at a Centennial Pizza Hut. He quit school after the 11th grade, the records indicate.

After his home life became unstable, Gartrell moved away from his parents at the age of 15, said Vanessa Sand, who said he found shelter at her home and couch for several months about 16 years ago.

Sand said Gartrell was nicknamed Thermos back then and that he never showed any violent tendencies.

“He was all about making music and making people happy and giving people a venue to forget their stuff,” Sand said.

Sand said that six years ago, she moved from the Denver area to Los Angeles. She said she kept in touch with Gartrell over the Internet but gradually lost close contact with him. Sand said she moved back to Denver about a year ago and has seen Gartrell sporadically since then.

She said that the group Gartrell was associated with when he was a teenager was “all rough and tumble kids, the skate punks of the town.” Still, she stressed there was no violence associated with anyone in the group.

“I’m still in shock,” Sand said. “He was always a loving and helpful friend.”

Johnson was arrested on a Greeley shoplifting warrant and for suspicion of drug dealing, according to CBI records.

Johnson was convicted in 2006 on an identify-theft charge. He also previously was arrested for forgery.

During his first appearance in court today, Johnson, wore blue jeans and a T-shirt which read, “If I don’t remember, It didn’t happen.”

Johnson’s mother, Karola, who today held a funeral for her husband, Dwaine Johnson, who died of bone cancer, said Nathan has paid dearly for bad decisions in his life but that he is no killer.

“My son would never do something like that,” she said referring to any attempt to kill Obama. “I know my son. That’s not him.”

She also said he has never been involved with white-supremacist groups. She said her son has been blackballed by law enforcement, but declined to elaborate.

She said he is a trucker who hauls gravel.

Kirk Mitchell: 303-954-1206 or kmitchell@denverpost.com