LOUISVILLE, Ky. — A federal jury has cleared four former coal company officials who were accused of skirting dust rules in two underground Kentucky mines.

The jury in U.S. District Court in Louisville deliberated Wednesday for about two hours before returning not guilty verdicts. The trial was a rare attempt to prosecute coal company officials on criminal charges.

Federal prosecutors had alleged that the men ordered subordinates to tamper with dust collection equipment at two Armstrong Coal mines in order to stay in compliance with federal regulations.

But defense attorneys said prosecutors lacked evidence that the men had taken part in a conspiracy to cheat the rules.

Kent Wicker, a Louisville attorney, said there “was never a scrap of evidence” that his client, Glendal “Buddy” Hardison, was guilty.

“We were gratified the jury understood,” Wicker said.

Hardison, the highest ranking company official of the four, was in charge of all of Armstrong’s western Kentucky mines. The coal company went bankrupt in 2017.

Eight people were originally charged in the case in 2018 and Hardison was added to the case in 2019. Five reached plea agreements with prosecutors to avoid felony charges.

Attorneys for the four men argued throughout the trial that the men took no part in rigging dust pumps and didn’t explicitly order anyone to break the rules.

The federal dust rules exist to protect mine workers from inhaling too much dusty air, which can contribute to an incurable and fatal disease called pneumoconiosis, or black lung. That disease has killed tens of thousands of coal miners.

By Associated Press