NEW YORK, JUNE 25 -- Imelda Marcos knew "dirty money" was used for investments that the former Philippine first lady and her husband made in the United States, a prosecutor told a jury in closing arguments today.

"She wasn't just an outside observer who had things happening around her that she didn't know about," Assistant U.S. Attorney Charles LaBella said. "Imelda Marcos was not in a glass tomb. She was not afraid to venture into the business world . . . She was in the thick of things."

Marcos, 60, has been on trial since March 20 on charges of racketeering, racketeering conspiracy, mail fraud and obstruction of justice.

The defense presented no witnesses because, Marcos attorney Gerry Spence said, "there was no case." Spence has said Marcos was unaware of any wheeling and dealing by her late husband, former Philippines president Ferdinand Marcos, and her codefendant, Saudi financier Adnan Khashoggi. He has also said the Marcoses invested in New York real estate in order to hide funds needed to guard against a communist takeover of the Philippines, an argument LaBella called "fiction."

Defense attorneys are to give their closing arguments Tuesday and Wednesday, and the case is expected to go to the U.S. District Court jury on Thursday.

The prosecutor today outlined what he called circumstantial evidence that proves Marcos and Khashoggi violated U.S. laws.

"Now you have the opportunity to put all the pieces together," LaBella said. The government alleges that the Marcoses looted their country's treasury of $222 million during their 20 years in power, investing some of the money in four New York office buildings, jewelry and artworks.

Khashoggi, 54, is accused of faking documents to help conceal the Marcoses' ownership of the real estate and paintings. That allegedly occurred after a U.S. court order froze their assets after their ouster from power in February 1986.

Witnesses described bribes and kickbacks from projects funded by a Japanese war reparation fund, "commissions" to the government-owned national oil company and fraudulent deals to exchange Philippine pesos to U.S. dollars through the country's central bank.

If convicted, Mrs. Marcos would face a maximum of 50 years in prison and a $1 million fine. Khashoggi faces a sentence of 10 years in prison and $500,000 in fines if convicted of mail fraud and obstruction of justice.