Senate Republicans are blocking several of President Obama's nominees – often for reasons unrelated to the position – resulting in vacancies at the Department of Labor, U.S. Environmental Protection Agency, Department of Justice, and elsewhere. In addition, the Democratic leadership has not often combated Republican tactics, as nominations have slipped down the list of Senate priorities.

At the Labor Department, several vacancies have hampered the administration's ability to advance its agenda, especially in the areas of occupational safety and health and worker rights.

On Aug. 5, President Obama nominated David Michaels to lead the Occupational Safety and Health Administration (OSHA). Michaels is an epidemiologist and professor at George Washington University, where he also runs the Project on Scientific Knowledge and Public Policy. A Republican-controlled Senate confirmed him in 1998 to serve as the Assistant Secretary for Environment, Safety and Health at the Department of Energy under President Clinton.

Michaels' nomination to OSHA is attracting scrutiny. Industry lobbyists fear Michaels would move aggressively to finalize new workplace health and safety standards. The Occupational Safety and Health Act, which OSHA enforces, directs the agency to write regulations "reasonably necessary or appropriate to provide safe or healthful employment and places of employment." The agency is a major focus for opponents of strong regulatory action on worker safety.

Industry lobbyists and conservative bloggers have also criticized Michaels' 2008 book, Doubt Is Their Product: How Industry's Assault on Science Threatens Your Health. In the book, Michaels details numerous examples – including tobacco, asbestos, and lead – where industry groups have commissioned scientific studies and reports intended to undermine evidence that would prove their products harmful or strengthen the case for regulation.

Several industry groups including the National Association of Manufacturers and the U.S. Chamber of Commerce have written to members of the Senate Health, Education, Labor, and Pensions (HELP) Committee highlighting their objections to Michaels' nomination and asking for a confirmation hearing in the committee. If the groups' concerns remain after the hearing, it is likely that senators will place holds on the nomination, a procedure by which one senator can single-handedly delay a bill or nomination.

A delay in Michaels' nomination will translate into additional delays in new OSHA standards and in revitalizing an agency that has been largely nonresponsive to worker safety issues. Critics of the Bush administration faulted OSHA for finalizing too few worker protection standards. As a result, there is a backlog of hazards in need of attention. OSHA Deputy Assistant Secretary and acting OSHA chief Jordan Barab has been making progress in trying to reduce the backlog: OSHA is developing a proposed rule to limit workers' exposure to diacetyl, a chemical used to give foods a buttery flavor, and the agency recently finalized a rule that would standardize the way employers communicate occupational hazards. However, OSHA is unlikely to shift into high gear without a full-time, Senate-confirmed head.

Republicans have also objected to M. Patricia Smith, President Obama's pick to be the Labor Department's solicitor general, the top enforcement official at the agency. After the Senate HELP committee approved Smith and reported her nomination to the full Senate, Sen. Mike Enzi (R-WY) announced a hold on the nomination.

Smith drew the ire of committee Republicans after she made an inaccurate statement during her confirmation hearing. Smith said she had not discussed expanding Wage Watch – a state-level program intended to crack down on wage and hour violations, which she ran while serving as the New York State labor commissioner – but later acknowledged that she had discussed expanding Wage Watch to the federal level.

The committee's Democratic staff called the error inadvertent. Committee chair Sen. Tom Harkin (D-IA) said Enzi's hold was "clearly an effort to try to delay the confirmation of the government's top advocate for our nation's workers," according to The New York Times.

Meanwhile, Lorelei Boylan has withdrawn her nomination to lead the Labor Department's Wage and Hour division amid conservative objections, according to The Washington Post. Boylan is also involved in New York's Wage Watch program. The Wage and Hour Division enforces minimum wage standards, child labor laws, and other worker rights issues. The Post reported that Boylan withdrew her nomination because of family issues, not because of Republican opposition.

Another Labor Department agency critical to worker protection, the Mine Safety and Health Administration, is also without a permanent leader. Joe Main, a safety official at the United Mine Workers of America, was nominated July 6. He has been approved by the Senate HELP committee and awaits a full Senate vote.

Key posts at the U.S. Environmental Protection Agency (EPA) also remain unfilled. In May, Obama nominated Paul Anastas, a green chemistry and green engineering expert, to lead EPA's main research office. The nomination has been delayed by Sen. David Vitter (R-LA), who is seeking a review of EPA's risk assessment for formaldehyde. EPA currently considers formaldehyde a "probable carcinogen" and is expected to update its scientific studies soon. The International Agency for Research on Cancer calls formaldehyde a "known carcinogen."

Sen. George Voinovich (R-OH) has placed a hold on the nomination of Robert Perciasepe to serve as EPA Deputy Administrator because Voinovich believes EPA has underestimated the potential costs of cap-and-trade legislation currently under consideration in Congress. The senator is requesting that EPA redo its economic analysis. He is using Perciasepe as a bargaining chip while acknowledging that, "This hold does not to serve [sic] as a reflection on Mr. Perciasepe's ability to perform in the role of the Deputy Administrator."

Voinovich's and Vitter's holds are part of a broader trend in which senators are holding nominees hostage not because of their qualifications but because of the lawmakers' objections to the views or policies of the administration. The holds are a simpler but more damaging alternative to traditional oversight mechanisms, such as hearings or letters of inquiry, as qualified candidates are kept out of their positions.

While Republicans have lodged complaints against nominees, Democrats have been slow to counter Republican arguments and unwilling to push back by scheduling votes. Instead, the nomination process appears to have fallen down the Senate agenda, behind other priorities like health care and FY 2010 spending legislation.

The pace at which the Senate is confirming nominees for the Obama administration is slowing. Between the spring and summer recess, the Senate confirmed an average of 18 nominees per week while in session. Since returning from the August recess, the average has dropped to less than nine per week, according to Senate and White House records.

Although Democrats hold a filibuster-proof majority, leadership has appeared unwilling to move to confirm nominees. Majority Leader Harry Reid (D-NV) has forced only two confirmation votes. One was on Cass Sunstein, the head of the White House Office of Information and Regulatory Affairs. The other was Thomas Perez, the Department of Justice's (DOJ) top civil rights lawyer. Republicans held up Perez's nomination after the Justice Department dismissed voter intimidation claims filed against the Black Panthers. The Senate confirmed Perez Oct. 6.

Perez was the first DOJ nominee to be considered by the Senate since April. Meanwhile, other Justice Department nominees accumulated: four critical assistant attorney general nominees await confirmation, including Ignacia Moreno, nominee for the environment and natural resources division; Mary Smith, nominee for the tax division; Dawn Johnsen, nominee for the Office of Legal Counsel (OLC); and Chris Schroeder, nominee for the Office of Legal Policy (OLP).

Johnsen's nomination has drawn criticism largely because of her past work with an abortion rights organization. Obama nominated Johnsen to head the OLC, a powerful office that provides the Attorney General and other administration officials with legal advice on almost any issue, on Feb. 11, making hers one of the longest outstanding nominations.

Obama nominated Schroeder on June 4. OLP provides high-level policy recommendations to the Attorney General and handles special projects and judicial nominations for the department. Schroeder is a law professor at Duke University and has written extensively on administrative and environmental law. He formerly served as a scholar at the Center for Progressive Reform, a collection of academics advocating for a regulatory system that better protects the public.

Parochial interests have slowed the nomination of Martha Johnson to serve as administrator of the General Services Administration (GSA) – the government agency responsible for procuring and managing real estate, equipment, and other assets. Currently, Missouri Sen. Kit Bond (R) has a hold on Johnson's nomination. Bond blames GSA for delays in the construction of a federal building in Kansas City, MO. Previously, Reid had slowed Johnson's nomination in an attempt to move a GSA-sponsored conference to Las Vegas in his home state of Nevada. Johnson was nominated May 4.