NOBODY EXPECTED Maryland Gov. Robert L. Ehrlich Jr.'s bipartisan cheer to endure much past the opening gavel in Annapolis, but his short fuse and inflammatory tactics are costing him dearly in the legislature. On Monday a Senate committee, irked by the governor's glib disdain for environmental groups, voted 10 to 9 to reject his nominee to head the Maryland Department of the Environment -- a stinging, unprecedented action against a governor's Cabinet choice. It was an overreaction, in our view, to Gov. Ehrlich's in-your-face tactics. His nominee, Lynn Buhl, a former automotive industry lawyer and environmental official from Michigan, may offend environmentalists because of her past ties to an agency that was lax in enforcing antipollution laws. But so far these opponents have failed to make a solid case. Barring further evidence, Ms. Buhl's nomination ought to be approved when it reaches the Senate floor this week.

The opposition probably wouldn't have had a chance to stop the nomination without Gov. Ehrlich's help. At her hearing, Ms. Buhl cited an 18-year record as a lawyer for the federal Environmental Protection Agency and DaimlerChrysler Corp. while playing down her four years as a mid-level administrator in the Michigan Department of Environmental Quality, an agency long under fire from environmental groups. Ms. Buhl said she worked over the years to prevent losses of wetlands, eliminate sewage spills and improve wastewater treatment plants. While this record may not satisfy the environmentalist lobbies, it hardly offers a basis for a historic departure from the legislature's deference to gubernatorial Cabinet choices.

Gov. Ehrlich, however, is proving to be his own worst enemy in Annapolis. His initial response to criticism of his selection was to go ballistic; his communications director, Paul E. Schurick, declared that the environmental activists had blown their chance to have "a seat at the table" in the administration. At her hearing Monday, Ms. Buhl testified that she had persuaded the governor to support a bill that is among activists' top priorities, to increase penalties for failure to control runoff from construction sites. But on Tuesday Gov. Ehrlich forbade administration officials from testifying in favor of the bill. Mr. Schurick said the governor could not be expected to support the legislation when his choice for secretary is in jeopardy.

The governor's appointments secretary, Lawrence J. Hogan Jr., accused Senate President Thomas V. Mike Miller Jr. of trying to kill Ms. Buhl's nomination so as to prove to the new Republican administration that the Democrat-controlled Senate must be reckoned with. Mr. Hogan claimed that Sen. Miller, who voted against the nomination in committee, told him weeks ago that the Senate would have to defeat one of Gov. Ehrlich's nominations on principle. Mr. Miller angrily responded that he had no recollection of such a statement.

We don't know who's right here, but between Gov. Ehrlich's brawling style and the Democrats' power-play response, the serious issues facing this year's legislature risk becoming mired in the mud.