The ruling centered on the little-known but centuries-old legal precedent of legislative immunity, which protects lawmakers from seeing their official work used against them in civil or criminal cases. The doctrine has proved controversial, particularly among federal prosecutors who have been stymied by it in numerous public corruption cases.
Sweeney, a retired Howard County judge presiding over the trio of Baltimore corruption cases, found that the state prosecutor was wrong to use votes and other legislative acts, such as favorable reports on bills, by Holton and Dixon to make his case before a city grand jury, which ultimately indicted them.
Legislative immunity - referred to federally as the "speech and debate clause" - can be traced to 16th-century British Parliament and has particularly deep roots in Maryland. Almost every state has similar protections for legislators, and Maryland's Declaration of Rights, adopted in 1867, explicitly prohibits courts from using state lawmakers' work against them.
State Prosecutor Robert A. Rohrbaugh said he will likely appeal the dismissal of Holton's case and is evaluating what to do in Dixon's. One option could be to seek new indictments without using the tainted evidence.
Holton was accused of billing developer Ronald H. Lipscomb for a $12,500 political poll in exchange for helping him secure tax breaks on multimillion-dollar city projects.
The dropped charges against Dixon were for perjury and misconduct in office for failing to report gifts she accepted from Lipscomb. Other charges of theft and misconduct in office, for allegedly taking gift cards meant for the poor, remain.
And Lipscomb will still face trial for allegedly bribing Holton. In fact, her votes can be used as evidence in his case because he's not an elected official.
To act without fearStephen H. Sachs, a former Maryland Attorney General and federal prosecutor, said the point of the protection for elected officials is to "assert the independence of the legislator."
"It's so that the legislator can act without fear that an executive, who is in a position to prosecute, can have him imprisoned for anything he does in his legislative capacity," Sachs said.
Other evidence, such as wiretaps or witnesses, is fair game in prosecuting an elected official.
But the case against Holton was built entirely around her voting record and involvement in City Council activities.
The Dixon case is murkier; it's not clear that her decisions as City Council president were needed as evidence to lead to a grand jury indictment on the four counts of perjury and one count of misconduct that were dismissed Thursday.
Rohrbaugh argued he didn't do anything wrong in telling the grand jury about Holton's and Dixon's legislative acts, asserting that immunity does not apply to local officials or in criminal cases.
But Sweeney sided with the defense argument, calling the protection for all levels of government officials "important pillars of our federal and state constitutions."
The judge also said Maryland common law - laws that are established through court cases rather than by legislation - supported his decision.
"The judge did a thorough job of analyzing the position of the state and our position, and we're very glad at the result," said Holton's attorney, Joshua R. Treem.
Maryland precedentsThe most similar case Treem cited in his motion to dismiss was from 1972, when a Maryland delegate was convicted of bribery for accepting $5,000 from bowling alley proprietors for helping to overturn a ban on the sale of alcohol at Montgomery County bowling alleys. The Court of Special Appeals threw out the conviction, finding it was based on the delegate's acts of sponsoring a bill and seeking support for the bill.
The federal provision on legislative privilege is the most tested - thanks in part to a 1963 bribery case against a congressman from Maryland's Eastern Shore.
Then-U.S. Attorney for Maryland Joseph Tydings won a conviction against U.S. Rep. Thomas F. Johnson, who accepted money to become a de facto spokesman for the savings and loan industry, even giving a speech industry officials had written for him.
On appeal, that conviction was overturned because giving speeches was part of his job as an elected official.
Federal prosecutors had argued unsuccessfully that Congress nullified its legislative immunity by passing laws against bribery.
"We in Maryland sort of invented the speech and debate clause litigation," said Sachs, who prosecuted Johnson the second time around, winning a conviction without the privileged evidence. "It didn't exist until our federal prosecutors began to bring cases."