Prince George’s County Council member Leslie Johnson was scheduled to plead guilty Wednesday in connection with a far-reaching corruption probe, but the hearing was canceled Monday.

Johnson (D-Mitchellville), 59, is accused of destroying evidence on the November day she and her husband, former county executive Jack B. Johnson (D), 61, were arrested as part of a federal investigation into whether public officials in the county accepted and solicited bribes.

Federal agents overhead Leslie Johnson on a wiretap conspiring with her husband to flush a developer’s $100,000 check down the toilet and hide $79,600 in her undergarments, according to court papers.

Sources familiar with the case said Leslie Johnson had been negotiating a plea deal with prosecutors, but it is not clear why a plea hearing set for Wednesday in U.S. District Court in Greenbelt was canceled. Plea agreements are not final until a defendant admits guilt in court and the agreement is approved by a judge.

Johnson has refused to discuss her case. Her attorney, Shawn M. Wright, did not return a phone call Monday or respond to an e-mail requesting comment. A spokeswoman for the U.S. attorney’s office declined to comment.

Johnson, a former administrative law judge who has been active in community groups, was elected to the council Nov. 2 and sworn in in December. If convicted of a felony, she would have to step down from her council seat.

Johnson has been active at public events and often is outspoken at council meetings. But the criminal charges against her prompted the full council to limit her duties. In December, the council took the unusual step of barring Johnson from sitting on committees, where dozens of key decisions are made. The council agreed she could attend committee meetings and vote on bills that come before the full nine-member body.

In recent weeks, Johnson has appeared at several public events.

On Saturday, she organized a community cleanup in her district. Last week, she attended a committee session considering County Executive Rushern L. Baker’s (D) proposed $50 million economic development fund and asked questions.

At a recent community music festival, Johnson said she plans to attend all of her district’s high school graduations this spring. “I look forward to working with all of you to ensure that all our children reach their full potential academically and creatively,” she said.

The case against her is part of a six-year corruption investigation that prosecutors say involves other county officials and business people. The probe revealed that developers and others had been “regularly providing things of value” to public officials in return for favors, prosecutors said.

In addition to Leslie and Jack Johnson, seven other people, including three Prince George’s County police officers, have been charged in connection with the broad investigation.

In March, federal prosecutors filed a criminal information charging Leslie Johnson with conspiracy to commit witness and evidence tampering, a legal step that typically signals that a defendant is preparing to enter a guilty plea.

At the time, sources familiar with the case said defense attorneys and prosecutors had not worked out all the details.

In February, Jack Johnson was indicted on charges of accepting $200,000 in bribes and of playing a central role in a broad corruption conspiracy. He has pleaded not guilty and has said he will fight the charges.