(Photo by Steve Shadley - KJZZ)

Dog owners hold photos of their pets that died in June 2014 at Green Acre Dog Boarding.

The owners of Green Acre Dog Boarding near Gilbert, where 21 dogs died of heat exhaustion a year ago, have pleaded not guilty to charges of animal cruelty.

Jesse and Maleisa Hughes entered their not guilty pleas today in Maricopa County Superior Court. Each faces a total of 29 counts of felony and misdemeanor animal cruelty and of felony fraud.

Prosecutors in January dismissed initial charges against the couple. However, following a new review of evidence, a new indictment against the couple was issued last month.

Defense lawyers said the deaths were a tragic and freak accident and there was no evidence of criminal conduct.