DENVER (AP) -- It took two years for federal prosecutors to bring criminal charges against the owners of a southeastern Colorado cantaloupe farm linked to a 2011 listeria epidemic that killed 33 people.
And the charges are little-used misdemeanor counts of introducing adulterated food into interstate commerce. Only four other people have faced such charges in the past decade, according to an attorney who specializes in food-safety cases.
Moments before brothers Eric and Ryan Jensen arrived in federal court in shackles Thursday to enter not-guilty pleas, a spokesman for federal prosecutors defended the slow-moving case.
Jeff Dorschner called the misdemeanor charges the "best, most serious charge we could find."
Asked why the Jensens were charged when few food-poisoning cases end up in criminal court, Dorschner said prosecutors in this case were compelled to act because the outbreak was so serious and widespread.
"It was the magnitude of the number of people who were hospitalized and the number of people who died," he said. Prosecutors said people in 28 states ate the cantaloupe, and 147 people were hospitalized.
Eric Jensen, 37, and Ryan Jensen, 33, wore khaki dress pants and collared dress shirts at their half-hour arraignment. They spoke little at the hearing but released a statement calling the outbreak a "terrible accident" and saying they were shocked and saddened by it.
The statement said the charges do not imply they knew about the contamination, or that they should have known about it.
The Jensens were released on unsecured bonds. Trial is scheduled for Dec. 2.
Only four other people have faced criminal charges in food poisoning cases in the U.S. in the past decade, said William Marler, who represents many of the listeria victims in civil cases against Jensen Farms.
Marler noted felony charges would have required prosecutors to show the contamination was intentional.
"The real significance of the case against the Jensens is they are being charged with misdemeanors, which do not require intent, just the fact that they shipped contaminated food using interstate commerce," he said.
The FDA has said the outbreak probably was caused by pools of water on the floor and old, hard-to-clean packing equipment at the Jensens' farm, which later filed for bankruptcy. The agency said investigators found positive listeria samples on equipment and fruit at the operation's packing facility.
The six separate charges correspond with six dates when the cantaloupe was put into the food supply, all in July and August of 2011.
The outbreak delivered a serious blow to farms in Colorado's revered Rocky Ford cantaloupe region, where hot, sunny days and cold nights produce fruit known for its distinct sweetness
Jensen Farms was about 90 miles away from Rocky Ford, but the Jensens used the Rocky Ford name, and sales dropped across the region. Later, Rocky Ford farmers registered Rocky Ford Cantaloupe as a trademark, hired a full-time food safety manager and built a central packing operation where melons are washed and rinsed.
Tammie Palmer, whose husband, Charles, became ill after eating the cantaloupe, said she hopes the Jensens never return to farming.
The Palmers, represented by Marler, filed a lawsuit against Jensen Farms seeking $2 million. The suit was still pending when Charles Palmer died this year of cancer.
"I was hoping everything would be settled and I could do something with my husband, but that's not going to happen," she said.
Associated Press writers Dan Elliott and Steven K. Paulson contributed to this report.