Two FBI agents were at the front door of their two-story brick colonial in Mitchellville.
"Don't answer it," the county executive said, unaware that more agents were listening in.
Johnson ordered his wife to find and destroy a $100,000 check from a real estate developer that was hidden in a box of liquor.
"Do you want me to put it down the toilet?" Leslie Johnson asked.
"Yes, flush that," the county executive said.
But what about the cash? she asked - $79,600.
Put it in your underwear, the county executive told his wife.
She replied, "I have it in my bra" - which is where agents discovered the money after she answered the door.
That conversation, as documented in an FBI affidavit, led to the arrest Friday of Jack Johnson and his wife. Each was charged with evidence tampering and destroying evidence in a case the U.S. attorney called the "tip of the iceberg" in a broader corruption investigation in Prince George's.
"We don't go on fishing expeditions," U.S. Attorney Rod Rosenstein said at a news conference. "We expect additional defendants and additional charges."
Appearing Friday night outside the federal courthouse in Greenbelt, Johnson vowed to fight.
"I'm innocent of these charges," he said. "I just can't wait for the facts to come out. When they come out, I'm absolutely convinced I'll be vindicated."
Johnson, 61, is in the waning days of his second term in office. His administration has been the target of allegations of cronyism and corruption since his 2002 election. He was silent as FBI agents led him and his wife separately from their home about 1 p.m. Johnson, the county's former chief prosecutor, wore a suit jacket on his shoulders, concealing his handcuffs.
Leslie Johnson, 58, who earlier this month won election to the Prince George's County Council, held a blue coat up over her face as an agent escorted her to a waiting sedan.
After a brief hearing, U.S. Magistrate Judge William Connolly ordered Jack Johnson released and placed under electronic monitoring. His wife was released on her own recognizance, and both were ordered to surrender their passports. The Johnsons each could face 20 years in prison if convicted.
The Johnsons' arrests grew out of a four-year FBI investigation into developers and their associates "regularly providing things of value to public officials" in exchange for official favors, according to a 10-page affidavit filed with the criminal complaint.
The investigation centered on alleged bribes Jack Johnson took in exchange for helping an unidentified developer seek grant money from a federal affordable-housing program administered by the county's Department of Housing and Community Development.
The developer gave Johnson cash and checks as far back as 2007, including one for $100,000, according to the affidavit. More recently, on Nov. 5, in what appears to be part of a sting, the developer gave Johnson $5,000 in cash in a transaction that investigators recorded.
On Friday, Johnson met again with the developer, who gave the county executive $15,000 in cash, the affidavit said. Following the payment, FBI agents confronted Johnson about the alleged bribe. Johnson explained that the money was for a "party marking the end of his term as county executive," according to the affidavit, written by FBI Special Agent Wendy H. Munoz.
The agents searched Johnson and found the $15,000 on him. The agents told the county executive they would not arrest him and that he could leave, but then they monitored his phone conversation with his wife.
After Leslie Johnson told her husband about the agents at the door, he urged her to find the $100,000 check and "Tear it up! That is the only thing you have to do," Munoz wrote, quoting the monitored conversation.
After she asked if she should flush the check down the toilet, agents listening to their call on a wiretap "overheard a flushing toilet. . . in the background," the document said.
Steve Willsey, a plumber who arrived at Johnson's home shortly after 1 p.m., said he was summoned by the FBI.
"I'm checking the toilet to make sure there is nothing in them," he explained. "So far I haven't found anything."
Jack Johnson was not charged with taking or soliciting the bribes outlined in the FBI affidavit, but prosecutors said in court that they weren't done.
"This is a very, very long investigation involving voluminous wiretaps and numerous cooperating witnesses," Assistant U.S. Attorney James A. Crowell said. "The case is likely to expand."
As agents descended on Johnson's home, federal investigators from the FBI and IRS also were executing search warrants at the Upper Marlboro headquarters of the Prince George's County government.
At least 12 warrants were served around the county, law enforcement sources said. Karen Campbell, a spokeswoman for the County Council, said she was unaware of any search warrants served at council members' homes or offices.
The arrests stunned Maryland's political world, in which Jack Johnson has been a player for a generation. Maryland Gov. Martin O'Malley (D) described it as a "sad day for Prince George's County and for County Executive Johnson and his family."
As the day's developments unfolded, the county government building roiled with speculation and anxiety about who else might be involved and what the investigation might yield.
Since taking office in 2002, Johnson has been criticized for doling out government contracts to friends and allies who were not qualified for the work and for running up excessive charges on his county-issued credit card. In 2008, federal agents investigating a real estate development in Greenbelt searched the offices of two of Johnson's senior advisers, as well as a campaign contributor.
David Byrd, the deputy chief administrative officer, and J. Michael Dougherty Jr., the county's director of finance, had their offices searched. Patrick Ricker, an investor in the Greenbelt project whose office also was raided during the investigation, held a $500-a-head fundraiser for Johnson in 2002.
Johnson also has been linked to a pay-to-play accusation involving a county contract to lease office space.
A Washington Post investigation of Johnson's first term in office found that he had given 15 friends and allies 51 county contracts totaling nearly $3.3 million.
The Post also found that Johnson and several County Council members charged thousands of dollars in personal expenses to their county-issued credit cards, revelations that prompted a state investigation into the spending and a new law requiring audits.
Johnson, a native of South Carolina who served as the county's state's attorney before becoming executive, personified Prince George's evolution from a majority-white suburb to a symbol of African American success. Johnson and his wife, the parents of three adult children, appeared on the cover of the New York Times magazine in 1992 for an article, titled "The New Black Suburbs," that focused on the migration of affluent African Americans from the District to Prince George's.
Johnson served as deputy state's attorney for two terms before winning election as Prince George's top prosecutor in 1994. Over the course of two terms as prosecutor, Johnson became a near-ubiquitous presence around the county, showing up at block parties and backyard barbecues, all the while laying a grass-roots groundwork for his successful campaign for county executive in 2002.
His near-constant criticism of Prince George's police department helped make him popular in the county's poor and working-class neighborhoods.
As county executive, he became known for raising Prince George's Wall Street bond rating and for seeking to improve its image with the slogan, "Gorgeous Prince George's."