Criminal defense lawyer Edward G. Varrone found the tables turned yesterday when he was called to the witness stand in Montgomery County Circuit Court to defend himself against a former client's allegations of incompetence.

Varrone, a partner in the D.C. law firm of Carter & Varrone, had been retained by Kalvin Stafford to defend him against first-degree murder and robbery charges in the Oct. 2 slaying of his 19-year-old girlfriend, whose body has never been found. Stafford told police he strangled Anita F. Bowling during an argument over money at her Silver Spring apartment and later disposed of the body in a trash bin 20 miles away in Columbia.

On April 4, Stafford agreed to plead guilty to second-degree murder, which carries a maximum sentence of 30 years in prison. Two months later, Stafford said he wanted to recant the plea agreement, alleging that Varrone was incompetent and that recent evidence suggested his girlfriend was still alive.

After a two-hour hearing, Judge William C. Miller, who had accepted Stafford's earlier guilty plea, denied Stafford's request to withdraw the plea agreement.

"The court is convinced that the plea was freely and voluntarily entered," Miller said. "It was ample evidence based on the defendant's confession, as well as other evidence that he's the one that committed the murder."

Varrone was called to testify as a witness for the prosecution to defend the plea bargain he negotiated for Stafford.

Swirling nervously in the chair, Varrone told Miller that while Stafford initially was reluctant to accept the plea bargain, he ultimately agreed to it in late March. Varrone also denied Stafford's claim that he had promised Stafford he could persuade Miller to give him a sentence of less than 30 years.

Stafford testified yesterday that Varrone had badgered him into accepting the plea bargain despite his reservations about the evidence against him. "The more I resisted, the more he became hostile," said Stafford. Stafford most recently claimed that a letter received several weeks after his plea said that his girlfriend was still alive.

Stafford, who is being held in the county jail, is scheduled to be sentenced Sept. 25.