A Democratic congressman plans to file a wide-ranging ethics complaint today against House Majority Leader Tom DeLay (R-Tex.), shattering the remnants of a seven-year-old, unwritten ethics truce between the two parties and possibly nudging the House back toward a brand of political warfare that helped topple two speakers.

The complaint, which Rep. Chris Bell (D-Tex.) said he will send to the House ethics committee, accuses the House's second-ranking Republican of soliciting campaign contributions in return for legislative favors; laundering illegal campaign contributions through a Texas political action committee; and improperly involving a federal agency in a Texas partisan matter. The House's top two Democrats raised no objections when Bell told them he would file the complaint, according to Bell's office and party leadership aides.

A grand jury in Austin has been looking into the Texas PAC's activities, although DeLay's aides say there is no evidence he is a target of the probe. DeLay has denied wrongdoing in all the matters cited in Bell's complaint.

"These are warmed-over and factually deficient allegations from a bitter partisan on his way out of office," DeLay spokesman Jonathan Grella said yesterday. "This election-year scorched-earth strategy is doomed to fail, as have all previous attempts of this cynical and sad sort that make a mockery of the process."

A DeLay ally, Rep. John T. Doolittle (R-Calif.), said Republicans "are going to have to respond in kind" by filing ethics charges against key Democrats. From now on, he said in an interview, it's a matter of "you kill my dog, I'll kill your cat." Doolittle said he plans to file ethics charges against a prominent Democrat but would not name the target.

Bell's main allegations have been aired before, but there is no evidence the ethics committee -- formally, the Committee on Standards of Official Conduct -- has looked into them. The panel must inquire into charges made by a House member.

Bell, a first-term lawmaker from Houston, lost his reelection bid in the March Democratic primary after his district was substantially redrawn in a contentious 2003 redistricting process backed by DeLay. Bell's loss was a byproduct, not a central goal, of the Republican plan because his redrawn district is more solidly Democratic than before. Neighboring districts, however, became more Republican.

Bell declined to be interviewed yesterday, but his spokesman, Eric Burns, said: "Nothing in this complaint is going to bring his seat in Congress back. This isn't about retaliation; it isn't about politics. It's about protecting the integrity of the House."

Bell's ethics complaint is the first known to be filed by a lawmaker against a House leader since 1997, when both parties agreed to an unwritten truce to end a long series of ethics charges and countercharges dating to the 1980s. The ethics war helped topple two speakers -- Democrat Jim Wright and Republican Newt Gingrich -- and helped the GOP take control of the House in 1994 after accusing Democrats of institutional corruption.

In recent years, some Democrats outside Congress have said the ethics truce was helping Republicans more than Democrats. Self-described watchdog groups berated the House ethics committee for its apparent inaction in a number of cases of questionable conduct raised in the news media and elsewhere.

Sources close to DeLay said House GOP leaders this week would discuss whether to encourage colleagues to file ethics complaints against Democrats or to keep quiet and assume Bell's charges will amount to nothing. Aides to House Minority Leader Nancy Pelosi (D-Calif.) and Minority Whip Steny H. Hoyer (D-Md.) said the two leaders neither encouraged nor discouraged Bell when he sent word of his plans to file the complaint. The 18-page document has three components.

Westar: Officers of Kansas-based Westar Energy wrote memos in 2002 citing their belief that $56,500 in campaign contributions to political committees associated with DeLay and other Republicans would get them "a seat at the table" where key legislation was being drafted. Bell's complaint says DeLay "illegally solicited and accepted political contributions in return for official action," but DeLay has said he did no such thing.

TRMPAC: Bell repeats earlier claims that the Texans for a Republican Majority Political Action Committee, created by DeLay, laundered $190,000 in corporate donations through the Republican National Committee, which sent $190,000 to Texas GOP candidates. State law bars such candidates from using corporate donations. DeLay and other Republicans deny the charges.

Federal Aviation Administration: Bell's complaint says DeLay "improperly used his office" when it asked the FAA to help locate a private plane last year. The plane was thought to be carrying Texas Democratic legislators who were preventing a quorum that Republicans needed in Austin to pass their contentious redistricting plan. DeLay has denied any wrongdoing.

Rep. Tom DeLay (R-Tex.) has denied wrongdoing in all the matters cited.