(PhysOrg.com) -- An alarmingly high number of Los Angeles County workers at the bottom of the labor market are the victims of "wage theft" and other workplace violations by employers, who on average deprive workers of 12.5 percent of their weekly paycheck, according to a study by three researchers with the Institute for Research on Labor and Employment.

Approximately 88 percent of those surveyed reported at least one instance of being paid less than the minimum wage, working overtime and not being paid for it, working off-the-clock for free, or other pay-based violation during the previous work week.

The results of a 2008 survey of 1,815 workers in the county holding such low-wage jobs as nannies, bank tellers, retail workers, garment workers, janitors and gardeners show that most of these violations are more prevalent in Los Angeles than in New York or Chicago, where similar surveys were done. Detailed, hour-long interviews were conducted with the workers who were asked to describe their previous work week.

"This is a wake-up call to the community," said Professor Ruth Milkman, lead author and a professor of sociology at UCLA and the City University of New York Graduate Center. Ana Luz Gonzalez, a doctoral candidate in urban planning, and Victor Narro, project director at the UCLA Downtown Labor Center and a lecturer in Chicano studies, are co-authors on the study.

Most egregious, said researchers, was that 30 percent of those surveyed in L.A. County were being paid less than the legal minimum wage for California, which is $8 an hour.

"I myself was shocked by that number," Milkman said. "We never dreamed we would find such a high prevalence rate. I don't think the average Angeleno has any idea that this is happening. We think this is outrageous and hope that the people in a position to do something about it will take action."

Minimum wage laws have set the basic standard of pay for U.S. workers since 1938, when Congress passed the Fair Labor Standards Act, which requires that employers pay workers at or above the minimum wage set by either federal or state law, whichever is higher. But many of the workers interviewed were unaware of the exact amount of the wage they were entitled to by law; when asked, only 50 percent of the L.A. respondents cited the correct minimum wage.

The UCLA researchers found high rates of other pay-related violations. Of those workers who reported working more than 40 hours for a single employer, 79 percent said they were not paid the legally required overtime rate. And 80 percent of the respondents reported they were not provided with meal breaks as required by law. California state law requires employers to provide most workers with an uninterrupted 30-minute meal break during any shift of five or more hours.

One of the most pervasive violations was that a majority of those interviewed in L.A. County, 64 percent, received no documentation of their earnings and deductions, as required by law, regardless of whether workers are paid in cash or by check. And 45 percent reported that their employers deducted from their pay for work-related tools, materials, uniforms, damage or loss, although California employers are generally not permitted to do so.

Another form of wage theft is off-the-clock violations, Milkman explained. One in seven of the L.A. respondents reported that they had worked before or after (or both) their regular shifts. And 71 percent of these off-the-clock workers were not paid for this work.

"In one interview, a retail described how she was required after every shift ended to deliver money from her till to another location. She was not paid for that time," Milkman said. A nursing home worker told interviewers that she was routinely asked by a supervisor to check in on patients after she had already clocked out.

The large number of undocumented immigrants in the Los Angeles County sample, 56 percent, underscores the vulnerability of these low-wage workers who may be afraid to report violations because of fear of deportation or other sanctions, researchers said.

But that factor and other worker characteristics proved not to be the strongest predictor of violations, Milkman said. These violations were more likely to occur in certain industries and occupations, such as the garment industry, home construction, car washes and domestic service. Job characteristics were four times more powerful in predicting minimum wage and overtime violations in L.A. County than worker characteristics were, the researchers found.

"Many employers have adopted business strategies that involve widespread noncompliance with the nation's long-established labor and employment laws," Milkman said. The nature of the low-wage labor market in Los Angeles is one that accepts and tolerates such violations. "A high number of employers in this part of the country have been operating in a 'wild west' atmosphere where the law is not considered to be a factor in how they operate," she said. "Employers currently think of legal penalties for violations as a cost of doing business."

While the number of federal enforcement personnel has been going down over the last 20 years, there is hope that enforcement may become a higher priority.

"U.S. Labor Secretary Hilda Solis has indicated that she is committed to enforcing the law," Milkman said. Solis represented East Los Angeles and San Garbriel Valley in Congress before President Obama appointed her as the top labor chief.

"That is a hopeful sign," Milkman said. "But it's like turning a big ocean liner around. It's going to take some time." Nevertheless, employers need to be put on notice that failure to comply with labor standards will no longer be tolerated, she said.

To read the full report, "Wage Theft and Workplace Violations in Los Angeles: The Failure of Employment and Labor Law for Low-Wage Workers," go here.