A former congressman and son of a prominent civil rights leader has been charged with spending campaign funds on personal expenses.
Jesse Jackson Jr of Illinois is accused of misusing $750,000 (£483,000).
The Democrat has not yet entered a plea but has released a statement accepting responsibility for "mistakes".
Mr Jackson, 47, resigned in November weeks after winning re-election, after acknowledging he was being treated for bipolar disorder.
"I offer no excuses for my conduct and I fully accept my responsibility for the improper decisions and mistakes I have made," Mr Jackson said.
Watches and fur capes
His wife, Sandi, has also been charged with one count of tax fraud, after prosecutors accused her of filing false joint tax returns.
She has pleaded guilty and has signed a plea agreement with prosecutors, her lawyer said.
Prosecutors said Mr Jackson "unlawfully, wilfully and knowingly combined, conspired, confederated and agreed" to commit offences against the US, according to court documents.
Prosecutors say that between 2007 and 2009 Mr Jackson used campaign funds to buy a gold-plated Rolex watch worth $43,350, fur capes and parkas worth $5,150, and about $9,588 in children's furniture.
He is also accused of failing to report $28,500 in gifts and loans to the House of Representatives, where he has served since 1995.
Mr Jackson, son of Chicago civil rights leader the Rev Jesse Jackson, faces a maximum penalty of five years in prison; his wife faces up to three years, according to federal sentencing guidelines.
But Mrs Jackson's lawyer said the plea deal "does not contemplate a sentence of that length".
Other penalties against Mr Jackson could include a fine of up to $250,000, US media report. In addition, authorities may try to seize more than $60,000 in memorabilia and furs linked to the alleged fraud.
Mr Jackson has also been under investigation by the House ethics committee over his dealings with jailed ex-Illinois Governor Rod Blagojevich, who was accused of trying to auction off President Barack Obama's former US Senate seat to the highest bidder.
Mr Jackson resigned from office on 21 November.