HARRISBURG -- A campaign operative is saying that former Republican House Speaker John Perzel paid him with campaign money to dig up dirt on fellow GOP members, including rivals for leadership positions.

Joseph T. Carduff of suburban Harrisburg made the allegation Friday in a letter to Rep. Curt Schroder, R-Chester.

Martin O'Rourke, spokesman for Mr. Perzel, said that's "absolutely false." The only research Mr. Carduff was told to do was on Democrats, he said.

Mr. Schroder, a seven-term lawmaker who voted against Mr. Perzel in the last speaker election, was among 10 Republicans that Mr. Carduff said Mr. Perzel wanted him to investigate earlier this year.

"It's just not true," Mr. O'Rourke said. "At no time did John Perzel direct him to do any kind of opposition research on any Republicans."

Mr. Carduff was to be paid $2,000 a month for opposition research, detailed reports on legal actions, voting records, legislative spending, personal relationships, property transactions, business dealings, criminal backgrounds and more. The reports, common in both parties, aim to collect information that reflects poorly on political opponents. Expenditure of campaign funds for such research is legal under state law.

Mr. Carduff said in his letter that he did not finish the work because he received only one monthly payment. He said he decided to alert the Republican subjects of his research because Mr. Perzel still owes him $2,000 and refuses to pay.

Mr. Carduff could not be reached for comment yesterday after his letter to Mr. Schroder was published on Capitolwire.com, a subscription-based political news service.

In the letter, Mr. Carduff said he approached Mr. Perzel in January, saying he wanted to return to political consulting after "two years of illness and incarceration brought on by my addiction to alcohol, which is now under control." He then met with other Perzel political advisers and was "quite surprised" when they directed him to create opposition portfolios for fellow Republicans.

Other Republicans Mr. Carduff says he was told to research included Republican Leader Sam Smith of Punxsutawney; Mike Turzai of Bradford Woods, who is planning to run for minority whip, the second-ranking job in the caucus; and Dennis O'Brien of Philadelphia, who defeated Mr. Perzel for speaker two years ago.

The other Republicans on the list were those who publicly criticized Mr. Perzel, voted against him in the 2006 speaker election or blocked him from other leadership positions that year.

"This is the kind of politics that the people of Pennsylvania are sick of," Mr. Smith said in a short statement issued last night.

Mr. Schroder said he was taken aback when Mr. Carduff first approached him.

"I thought it was a pretty incredible story, but the whole thing has a ring of truth to it," he said last night. "There's been such a pattern of operations and skulduggery in the past that I don't find it difficult to believe."

He said Mr. Perzel could have used the research to keep caucus members in line or to help primary candidates who would support him in the caucus.

"There's power in that kind of information. If you're a threat to [Mr. Perzel] or you're someone standing in his way, that kind of stuff can be used to neutralize you, to put you in your place," Mr. Schroder said. "We can't operate that way and expect to thrive as a caucus. Individual members should be able to take stands and do things without fear of that kind of internal retribution."

Mr. Turzai and Mr. O'Brien could not be reached. Most lawmakers were not in their state offices yesterday because of the Veterans Day holiday.