The government put investment banker Nathan A. Chapman Jr. "out of business" in a failed effort to snare state officials in a larger political corruption case, a defense attorney said in final arguments Thursday at Chapman's federal fraud trial.

Attorney William R. "Billy" Martin told jurors that the government had "ruined a lot of lives" in prosecuting the prominent financier for what amounted to failing to "cross his 't's and dot his 'i's." Martin said the charges resulted from minor mistakes that should have been resolved in civil court.

Prosecutors went after Chapman, a money manager whose portfolio once included $140 million from the state pension fund, as part of an effort to "get" former governor Parris N. Glendening (D), Martin said.

Prosecutors used their closing arguments to review three fraud schemes central to the charges and urged jurors not to be "distracted by any attempts to cloud" the evidence presented over seven weeks.

Chapman is charged with 32 felony counts -- mail fraud, wire fraud, investment advisory fraud and other offenses. He is accused of investing a portion of the pension money in his companies, losing nearly $5 million from the fund in the process, and looting more than $500,000 from the companies over five years.

Martin noted that the primary FBI agent on the case works in a public corruption squad and said there would be no case against Chapman if prosecutors and the FBI "had not found the need to get" Glendening.

"The government wanted to find out what Nate Chapman was doing with the governor," Martin said.

Martin also said evidence that Chapman lavished gifts and cash on mistresses was introduced only because it was salacious, because it might inflame jurors enough to treat as criminal offenses what Martin suggested were accounting errors and, perhaps, a breach of contract.

"Because it might make you mad enough to think there must be something there," Martin told jurors in U.S. District Court here. "What you have is a civil breach of contract, but if they can dirty [Chapman] up, make you mad, then he's going down."

Martin added, "Ladies and gentlemen, I would hope that you find it repulsive to drag these young women in here when it was not necessary."

Three women testified that they had affairs with Chapman.

Prosecutors disputed Martin's contention that the case was driven by an interest in the former governor.

"This case developed because of Mr. Chapman's actions," Assistant U.S. Attorney Craig M. Wolff said. "It didn't develop because Mr. Chapman was a steppingstone to anybody else. Don't be distracted by any attempt to cloud the case."

In addition to looting his companies and mishandling the pension money, Chapman is accused of arranging for one mistress to be named a pension trustee, which enabled her to promote his interests. The mistress, Debra B. Humphries, has pleaded guilty to lying to a grand jury and acknowledged filing financial disclosure forms that failed to mention cash and gifts from Chapman worth more than $45,000.

Assistant U.S. Attorney Jefferson M. Gray told the jury that he has known Martin for 16 years and that the defense attorney's attacks on the government's motives "pain me personally."

Gray said the case "richly deserves" to be in a criminal court. The prosecutor argued that Chapman failed in his responsibility to act solely in the interest of the pension fund when he invested in his companies and that he failed to act in the interest of his shareholders when he used business development checks improperly.

The case is important, Gray said, because money managers must be trustworthy. It is important "for all of us who have to rely on these strangers to act solely in our best interest, never to take their interests into account at all. Did Mr. Chapman do that? Of course not."

The jury is scheduled to begin deliberations Monday.

Nathan A. Chapman Jr., center, walks to court in Baltimore with defense attorneys, including Nathaniel Jones and William R. "Billy" Martin, right.