Missouri family sue Yellowstone National Park and Wyoming sheriff after they were held at GUNPOINT for an hour when dad was mistaken for triple-murder suspect

Yellowstone National Park rangers and Wyoming sheriff's deputies seeking a murder suspect mistakenly held a vacationing family at gunpoint for an hour, a lawsuit claims.

Brett and Genalyn Hemry, of Independence, Missouri, were vacationing in 2017 with their seven-year-old daughter in Yellowstone where park rangers and local sheriff's deputies mistook Brett for triple-murder suspect Gerald Michael Bullinger.

The couple say they and their daughter were held at gunpoint for an hour before cops allowed Brett to show his ID and prove he is not the alleged killer.

The family say they were victims of false arrest, excessive use of force and false imprisonment.

A federal lawsuit, filed July 19 in US District Court in Cheyenne, seeks unspecified damages to be determined at trial. 

Law enforcement officers at the time of the encounter were seeking Bullinger, a Utah man suspected of killing his wife Cheryl Baker, his girlfriend Nadja Medley and her 14-year-old daughter Payton in Idaho. 

Bullinger's whereabouts remain unknown. 

A family vacationing in Yellowstone National Park says they were held at gunpoint in 2017 by park rangers and local county sheriff's deputies, who allegedly mistook the father for a triple-murder suspect, according to a federal lawsuit 

The suit alleges that the rangers and sheriff's deputies mistook vacationing father Brett Hemly for Gerald Michael Bullinger who is accused of murdering his wife, girlfriend and girlfriend's daughter 

Investigators had found a car Bullinger was driving in Bridger-Teton National Forest outside Moran, near Grand Teton National Park in western Wyoming, on July 12, 2017.

In their suit, the Hemrys say that on July 20, 2017 they were driving in their family SUV out of Yellowstone's east gate, when two park rangers in separate vehicles began to follow close behind, prompting Brett Hemry to pull over about 15 miles east of the park. 

The rangers had allegedly flagged the SUV as one Bullinger may have been driving. 

After the family stopped, the rangers then allegedly pulled in front of the family's SUV, blocking it, and held the family at gunpoint, ordering them to drop their car keys outside and keep their hands up.

More officers arrived, including Park County sheriff's deputies, and officers then held the three family members at gunpoint in separate vehicles, the lawsuit alleges.

About an hour after being pulled over, officers allowed Brett Hemry to show his identification. 

They then told him they were seeking a murder suspect and showed him a photo of Bullinger, the lawsuit alleges.

Hemry 'bore no resemblance' to Bullinger except for his light hair color, the lawsuit claims.

'The terrified family went on its way, without receiving an apology or additional explanation,' the lawsuit states.

The suit also alleges that Brett Hemly looks nothing like Bullinger, except that they both have grey hair 

Park County Sheriff Scott Steward declined to comment on the pending litigation. 

Yellowstone officials said they do not comment on pending litigation.

Authorities had been looking for Bullinger since the bodies of Baker, 57, Medley, 47, and Payton were found shot and covered with plastic in a shed on June 19, 2017.   

Bullinger, a commercial jet pilot, is believed to have been having an affair with Nadja, the widow his late brother Tom, and was living with her and Payton in Idaho. 

Meanwhile, Baker, a recently retired school teacher, decided to take a surprise trip from Utah, where they were selling their family home, to visit to her husband in Idaho.

He had told her he living alone there in a trailer while fixing up a rundown property for them to move into. 

Bullinger with his girlfriend Najda Medley and her daughter Peyton. He is accused of killing the two in 2017

Bullinger with his wife Cheryl Baker. He is also accused of her murder, and has not been found

What happened after the surprise visit is unknown, and four years later Bullinger has not been found. 

Colleague Julie Grose said they last saw Baker – who was a veteran teacher with 30 years experience - at the school on June 6 for her last day.

'We had a meeting to say goodbye and Cheryl was talking about her retirement and the farm. She told us about a shed on the property that she planned to convert into an art studio, she was passionate about art.

'She seemed so happy talking about it, it is very sad. Why would she have said that if she knew about this other woman, she was never phony, she never said anything to upset people.'

Drake added: 'She was a wonderful teacher and gave so much, she will be missed.'