A federal judge has refused to grant new trials to three drug dealers whose cases were handled by a drug agent who was acquitted of charges that he framed more than a dozen suspects in a separate botched drug raid.

U.S. District Judge James Gwin ruled Wednesday that, while he did not approve of the way the government handled their cases, the defendants failed to show prejudice in their original trials.

Carl Henderson, Gerald Taylor and Maurion Lewis were each sentenced to more than 10 years in prison. They were arrested in 2007 following a sting by federal agents and police, who recovered seven kilos of PCP from a hotel room in Brooklyn, a Cleveland suburb.

The defendants had asked for new trials on the grounds that the government failed to disclose evidence they could have used to impeach Drug Enforcement Agent Lee Lucas, who was the government witness in their trials.

Messages seeking comment were left after business hours with the federal public defender's office.

Lucas was acquitted in February of all charges in a botched 2005 drug raid meant to clean up the drug trade in Mansfield, a blue-collar city of roughly 50,000 residents about halfway between Cleveland and Columbus.

Lucas was accused of using an informant to make controlled drug buys, then putting false information in his reports about the transactions. He was acquitted in February of all 18 counts against him, including obstruction of justice, perjury and deprivation of civil rights.

Defense lawyers for the three convicted dealers have said the federal prosecutor's office failed to turn over evidence against Lucas before their clients' 2007 trials. They said prosecutors routinely went out of their way to protect Lucas' image and cloak it in secrecy, fearing that adverse attention would allow lawyers to attack his credibility on the stand.

The undisclosed evidence included a court's observation that Lucas intentionally misrepresented facts in a search warrant affidavit, allegedly abused suspects and performed unconstitutional searches, and allegedly perjured testimony before a grand jury, according to the judge's ruling.

Had Lucas' testimony been discredited, the defendants argued, they would not have been convicted.

But because untainted evidence corroborated Lucas' testimony used to convict the defendants, Gwin wrote, the government's failure to disclose the evidence did not prejudice their cases.

Though he dismissed the motion, Gwin was blunt in his criticism of the U.S. attorney's office.

"The government made disturbing efforts to defend Agent Lucas's credibility against growing evidence to the contrary," he wrote.

Messages seeking comment were left after business hours with the U.S. attorney's office.