Here's that video by Dirk Friel, a cyclist from Boulder who filmed Ernst's strange behavior and posted it under the title, "Insane Driver who obviously doesn't like people on bikes."
As we've reported, Friel, 42, was cycling with a friend on East County Line Road in Longmont on September 16 when Ernst allegedly began harassing them. In the video, it's apparent that the SUV has room to pass and the cyclists are staying far to the right, giving him plenty of space to do so.
Friel, who lives in Boulder and is the founder of Trainingpeaks.com, a Colorado company that works with athletes, is riding single file in front of his friend and expresses his disbelief at the situation during the two-minute video -- but he says the bike-rage went on for longer.
Both the cyclists tried to wave Ernst past. They say that after about five minutes, he finally drove by.
The pair went on with their Sunday ride and didn't alert law enforcement officials immediately, though Friel did post the video on YouTube and Twitter. Once the clip began to go viral, he decided to contact the Colorado State Patrol, which led to the charges against Ernst.
In total, Ernst faced three charges related to aggressive driving. One was a misdemeanor harassment charge for following the cyclists, while the other two were for traffic infraction: driving too slowly and inappropriate honking.
On Friday, Ernst pleaded not guilty to all three charges, a Colorado Judicial Department spokesman says.
Continue to read more about James Ernst's plea in the bike-rage incident. For his part, Friel says he hasn't been following developments too closely -- but he isn't surprised the driver says he's innocent."This is probably to be expected, because people tend to go in and try to talk down charges against them," he notes.
Friel says it's still shocking to him that a normal weekend bike trip could have resulted in such drama.
"I guess I'm just amazed that my leisurely Sunday morning ride has to lead to a day like this," he says. "It's just too bad that...it had to end up like this when, to the letter of the law, the cyclists did exactly what they were supposed to do."
Ernst's guilty plea comes just a week after a similar alleged harassment case made headlines. In it, a Deer Creek Canyon driver in a Ford Ranger honked at a group of cyclists, eventually knocking one to the ground and crushing his bike.
The silver lining to Friel's case, he says, is that in the wake of the high-profile incident, more people are talking about the need for better behavior on the road.
"It's good for cyclists' rights to get the word out there that we should all share the road together, cohesively," he says, adding, "I think there's quite a bunch of evidence on our side."
He hopes the story doesn't discourage people from cycling as a mode of transportation.
"Every employer in the state of Colorado should encourage their employees to ride to work," he says. "I want more people on their bikes on the road."
More from our Colorado Crimes archive: "James Holmes: Inmate's strange tale of "confession" and suicide efforts"