SEIU spokeswoman Hilary Haycock said the investigation began after candidates who lost their bids for offices within the union complained to federal officials.

Deanne Amaden, a spokeswoman with the U.S. Department of Labor, said the agency's policy is to neither confirm nor deny ongoing investigations. She declined to comment further.

Haycock said she wasn't certain when the department would issue its findings, but she noted the bureau extended its deadline for gathering evidence to May.

Gregory Kamer, a partner in the labor law firm Kamer Zucker Abbott, said allegations of union use of employer dollars in elections is uncommon in Nevada.

The charges are serious, he said, because the Labor Management Reporting and Disclosure Act of 1959 prohibits direct contributions from private-sector employers to unions.

The law designates such violations as felonies, Kamer said, and penalties include up to $15,000 in fines or up to five years in prison, or both.

The federal government's investigation into the SEIU has become fodder for the California Nurses Association/National Nurses Organizing Committee, which is tangling with the SEIU over representation of nurses at the three hospitals in the local St. Rose Dominican health-care system.

The CNA issued a series of statements Tuesday blasting the SEIU over the department's investigation, calling the charges "the latest in a pattern of corruption and violence emanating from the top leadership" of the SEIU.

"They're taking money from employees, the people they negotiate with, and using it to run a slate of candidates," said Fernando Losada, collective bargaining director of the National Nurses Organizing Committee and head of the effort to gather Southern Nevada members. "It's the worst type of conflict."

The CNA began its current bid to represent local nurses in late 2007.

That's when SEIU-covered nurses at St. Rose Dominican started talks for new contracts with the SEIU. Some of those nurses reached out to the CNA and asked for the opportunity to join, Losada said.

The nurses are scheduled to vote on their union representation May 6 and 7.

The CNA has already made strides with nurses at a St. Rose Dominican sister hospital in Northern Nevada.

About 500 nurses at Reno's St. Mary's Hospital, which belongs to St. Rose Dominican parent Catholic Healthcare West, joined the CNA four months ago. The CNA also represents about 10,000 other nurses at Catholic Healthcare West hospitals across the region. CNA officials plan to meet with nurses at other local hospitals as well, after the May elections conclude, Losada said.

Haycock said the CNA's take on the Labor Department's investigation shows the competing union's officials "clearly don't understand the investigation."

"It's another example of the CNA using hyperbolic language, completely distorting the truth and really hurting the ability of workers both here and across the country to achieve the goals workers want to achieve, which is to improve working conditions, build the American dream and improve health care in Las Vegas," she said. "They're trying to organize nurses here, and they're willing to say or do anything to destroy the powerful union that Nevada's health-care workers and public-service workers have built."

Haycock added that SEIU officials are "pretty confident" that the Department of Labor will certify the union's election was legal.

Contact reporter Jennifer Robison at jrobison@reviewjournal.com or 702-380-4512.