In the recorded conversations played Thursday in federal court, disgraced former Henry County Sheriff Frank Cassell seemed almost grandfatherly as he reached out to reassure a one-time employee down on his luck.

But what the ex-deputy was telling Henry County's top cop -- repeatedly -- was that he'd stolen cocaine and sold it. And Cassell's response was to say that it was OK, that no one needed to know about it.

In November, that disregard for other officers' wrongdoing ended Cassell's nearly half-century in law enforcement.

On Thursday, his guilty plea in U.S. District Court in Roanoke made Cassell the 17th of 20 defendants to be convicted in a case that shook Henry County.

"It's a sad day for this community any time a leader in law enforcement crosses that line," U.S. Attorney John Brownlee said after Cassell's plea.

Brownlee called the Henry County charges the latest in a years-long series of public corruption cases prosecuted by his office that included conviction of Lynchburg's mayor on fraud and other charges, and Buchanan County officials in a bribery scandal that revolved in part around coon hunting.

"People deserve to live in honest communities," Brownlee said.

Charges like those against Cassell "are not easy cases for us in law enforcement," added Kevin Foust, who supervises the FBI's Roanoke office. "But that is our job to do."

Cassell, a 69-year-old Axton resident who spent decades as a Virginia state trooper before becoming sheriff in 1992, received national television coverage after the 2002 slayings of Michael and Mary Short and their 9-year-old daughter, Jennifer. It was the highest-profile case of his career and remains unsolved.

Last year he became the senior figure in charges that entangled a dozen members of his department, a state probation officer, a postal worker and five other people. Accusations included theft, drug use, firearms violations and an attempted cover-up.

Facing five charges -- making a false statement to an investigator, money laundering, concealing a felony and two counts of trying to obstruct justice -- Cassell pleaded guilty to making a false statement in return for having the other counts dropped.

"Frank acknowledged his own actions and accepted responsibility," said John Lichtenstein, one of three attorneys representing Cassell. "He is truly sorry ... and now he will begin to address his future."

The charge to which Cassell pleaded guilty carries a maximum sentence of five years in prison, a $250,000 fine and a period of supervised release. His plea agreement does not recommend a penalty, but sentencing guidelines range from six to 12 months behind bars.

Exchanges in and out of the courtroom Thursday indicate that arguments at Cassell's sentencing hearing, which is not yet scheduled, will pit portrayals of the sheriff's character against the bare facts of his actions. Was Cassell duped when deputy-turned-informant James Alden Vaught came to him saying that he'd resigned because of shame, but now was having trouble caring for his sick wife and children? Or was the sheriff ignoring his duty and protecting a criminal when he told investigators he didn't know -- though Vaught was recorded telling him -- that the former officer made $10,000 selling drugs?

After Cassell pleaded guilty, Lichtenstein noted Vaught's hard-luck story and described it as context for the many recordings played by Assistant U.S. Attorney Tom Bondurant Jr.

Bondurant replied that when Cassell heard Vaught admit to drug dealing and speculate about money laundering, he should not have let it pass.

Sure the sheriff was set up, Bondurant said after the hearing, but that's what investigators do.

"Just because he's in law enforcement doesn't mean he gets a free pass on that," Bondurant said of Cassell.

On the recordings played in court, Cassell tells Vaught he will not tell anyone about Vaught's actions and advises him not to talk about them.

"The older I get, the more I see of life, the more I realize human frailty -- I don't expect everybody to be perfect," Cassell said on a recording.

Prosecutors have described the Henry County case as a web of corruption that began to unravel in March 2005. Agents from the Philadelphia office of the federal Drug Enforcement Administration contacted counterparts in Roanoke to say they knew a package of ketamine was being mailed to a Martinsville residence.

Ketamine is an animal tranquilizer that is sometimes taken recreationally. It is known as a "date-rape drug" because it can render someone semiconscious and impair memory.

Agents intercepted the package and delivered it themselves. Then they arrested William Randall Reed and charged him with possessing ketamine with intent to distribute it.

Reed began helping investigators, who found that the Martinsville residence Reed used to accept the drugs was a rental property owned by Vaught, a sergeant with the Henry County Sheriff's Office. Reed said he paid Vaught in cash and ketamine.

Reed also said he helped Vaught sell 2 kilograms of cocaine the officer had seized during a case.

Vaught also began assisting investigators and recorded conversations with many of the defendants. Eventually, investigators pieced together a description of officers using and selling ketamine and steroids, using Vaught's rental house for extramarital affairs, and distributing cocaine, crack and hundreds of pounds of marijuana.

False destruction orders were filed for drugs seized as evidence, prosecutors said, and then the drugs were sold. Drugs used to train drug-sniffing dogs also were sold.

Guns, money, lawn mowers, tools and electronic equipment were stolen from the sheriff's office, prosecutors said.

Three officers have pleaded not guilty and are scheduled for jury trials. None of the defendants in the case has been sentenced yet.