Nearly three years into a City Hall corruption probe, the only charges leveled so far against an elected official appear difficult to prove, veteran attorneys said yesterday. And some wondered why a prominent developer also indicted would resort to a questionable political payment, given his long experience using campaign finance loopholes.

Baltimore City Councilwoman Helen L. Holton stands accused of accepting a bribe from developer Ronald H. Lipscomb in exchange for tax breaks on valuable waterfront property at Harbor East, a prime redevelopment neighborhood.

Prosecutors face a steep challenge in convincing jurors that Lipscomb tried to influence Holton's decisions by paying $12,500 for a political poll before a city primary, said David Irwin, a Baltimore attorney with more than two decades of experience as a white-collar attorney. "There are other plausible scenarios. Was he getting anything for this, or was he paying because he's a nice guy?"

"And would the outcome [of City Council votes] have changed had he not paid? This is an obvious project, helping Baltimore City," Irwin said, theorizing defense strategies. Irwin is not representing anyone in the case.

Bribery is the only charge filed by state prosecutors this week against Lipscomb and the most significant of four charges against Holton, carrying a maximum penalty of 12 years in prison.

This week's indictment stunned City Hall observers who had long expected that prosecutors were weighing charges against Mayor Sheila Dixon, who had a personal relationship with Lipscomb.

The Baltimore grand jury hearing evidence from State Prosecutor Robert A. Rohrbaugh will be dismissed today. It has reached the end of its four-month term, and more indictments are possible.

Holton was removed yesterday from her post as head of a powerful city tax breaks committee, a day after being indicted on charges that included perjury and malfeasance.

The West Baltimore Democrat became chairwoman of the Taxation, Finance and Economic Development Committee in January 2007, after serving for years on another City Council finance committee. Those committees awarded millions of dollars in tax breaks to the Inner Harbor East project, in which Lipscomb had a financial stake.

Holton and Lipscomb have said through their attorneys that they are innocent.

Lipscomb, 52, and Holton, 48, are scheduled for their first appearance in Baltimore Circuit Court in early February, when they will enter pleas.

As their cases proceed, the challenge for prosecutors will be to keep the presentation "simple and focused," said Isabel Cumming, head of economic crimes for the Prince George's County state's attorney's office and a former state prosecutor. She praised Deputy State Prosecutor Thomas "Mike" McDonough, the lead prosecutor in the Holton-Lipscomb case, calling him "methodical."

McDonough has been a state prosecutor since 1984 and has worked on numerous high-profile public corruption cases.

University of Baltimore law professor Byron L. Warnken said the case is a good example of the cynical view that there is a fine line between lobbying and bribery. "If I'm defense counsel, I'm saying to the jury, 'Look, anybody who is dealing with the government is constantly trying to meet with politicians, call them, give money to them. It's how the system works.'"

To prove the bribery charges, Warnken said, prosecutors will have to show that the $12,500 was spent explicitly to buy Holton's favor.

Campaign finance rules allow businesses or people to contribute $4,000 per election cycle. Major donors - particularly developers - have routinely funneled contributions through limited liability corporations with slightly different ownership structures, thereby avoiding the limits.

Over two campaign cycles, Holton received $11,500 from Lipscomb, his wife, Zaiafanice, and limited liability corporations listed in court papers as affiliated with Lipscomb, campaign finance records show.

Lipscomb and businesses connected with him have given almost $500,000 to politicians, nearly all Democrats, over the past 10 years, records show.

By contributing through a multitude of limited liability corporations, as Lipscomb has done for years, a developer can increase his giving power dozens of times over. The key technicality is that each LLC must have a slightly different ownership structure.