EVERETT, Wash. -- Five people who blocked an oil train in Everett in September 2014 finished their testimony in trial Wednesday.

"Powerful" was how Abby Brockway described to jurors what it felt like to be 18-feet high above railroad tracks. She topped a tripod formation with four others locked to the base. It forced an oil train to stop in Everett for eight hours.

"I wanted to stay longer, but because I was a mother, I decided that was enough. I'd made enough of a point," Brockway said.

The point she and her co-defendants wanted to make was that oil trains pose imminent danger. Expert witnesses called by the defense testified to the risk of oil by rail and fossil fuels' acceleration of climate change.

"Not inevitable, but it is irreversible. Once we do it, we say, 'Oh ok, those guys were right, let's do something.' Too late," explained former University of Washington professor and climate expert Richard Gammon. "We've loaded the dice. We've changed the odds. It's like, 'Which cigarette gave me lung cancer? Which bottle of whiskey wrecked my liver?'"

The Pacific Northwest has become a booming global fossil fuel hub, according to Eric de Place, who studies coal and oil exports at Sightline.

"There is such intense pressure from coal, oil, and gas companies to move their product through this region," de Place said. "We have also seen them derail and explode catastrophically 10 times in the last 2.5 years."

De Place says that government safety regulations are "woefully lacking." That's why the so-called Delta 5 argues they had no choice after years of legal protests, attending hearings, even writing legislators and President Obama.

The prosecuting attorney asked several times if there is scientific evidence to support whether civil disobedience is more effective than protests done legally. The necessity defense the Delta 5 are using argues that their illegal action was necessary to stop an imminent danger for the greater good.

"It felt like projects were being rubber stamped, no matter what we did," Brockway said. "Before I switched to direct action, I felt like I tried to work within the system to the fullest extent possible."

If jurors decide in favor of the Delta 5, it could set a historic, legal precedent. The decision would affirm climate change as an imminent threat, one that in this case necessitated breaking the law.