Applying for a job at Wal-Mart? Be prepared to disclose everything about your sordid past.

That's the new drill at the mega-retailer, which will start running criminal background checks on applicants this fall. The company said it has no plans to run checks on its thousands of current employees.

The retailer's announcement this month triggered a wave of discussion and surprise, but it probably shouldn't have.

According to a study released by the Society for Human Resource Management in January, 80 percent of 270 companies surveyed -- which included manufacturing, insurance and retail industries, among others -- say they conduct criminal background checks on employees. That's up from 51 percent in 1996.

Why the increase? Employees in government contracting and defense have always had to go through stringent background checks. But, as we keep being told, the world changed after Sept. 11, 2001, and many companies like Wal-Mart seem to be trying to keep up with it. But there's more. Lawsuits against companies for employee behavior have increased. And background-check technology has made the process cheaper and easier.

The Bentonville, Ark., retailer isn't saying much about why it began testing the process a year ago. It was part of a "standard review we do on all practices and policies," said spokesman Gus Whitcomb.

But the announcement comes on the heels of two sexual assault cases involving Wal-Mart employees and children. In both cases, the accused molesters had earlier convictions related to sexual offenses, something that would likely have been caught with a criminal background check.

"Typically, in part because it was time-consuming and cost-prohibitive, [retailers] restricted [background checks] to key positions or those who had access to high levels of cash," said Daniel Butler, vice president of retail operations at the National Retail Federation. "What we're seeing over time is a tool that is becoming more available and more affordable."

Usually, larger organizations set up a kiosk or computer terminal in their hiring department to do the checks. Potential employees enter their name, date of birth, Social Security number and current and former addresses.

The background software checks the information given against several databases to look for arrest records. That information automatically goes back to the hiring manager, according to James E. Lee, chief marketing officer at ChoicePoint Inc. near Atlanta.

ChoicePoint has been named by several sources as the company that will do Wal-Mart's checks, but neither Wal-Mart nor ChoicePoint would confirm this.

"In . . . such a litigious society, I'm blown away they weren't doing background checks on frontline employees, the ones who have contact with the public. From a liability perspective, that's amazing," said Jared Callahan, sales director at Employment Screening Resources, a human resource consulting firm that specializes in background screenings.

Although the thought of a criminal check may leave some shaking in their shoes, it doesn't necessarily mean they won't be able to sell, well, shoes. Companies that do checks typically disqualify people based on specifics. So if someone has a DUI conviction, companies like Wal-Mart will probably still let them sell discount stone-washed jeans and camouflage parkas. Of course, they probably won't have much luck getting a job driving a truck.

But some people wonder whether such checks are legal.

According to the Equal Employment Opportunity Commission, while doing background checks is legal, the company has to be careful that its disqualification of those with records does not translate into racial discrimination, as has been argued in courts, said Dianna Johnston, assistant legal counsel at the EEOC.

According to an EEOC policy guidance, "since the use of arrest records as an absolute bar to employment has a disparate impact on some protected groups, such records alone cannot be used to routinely exclude persons from employment."

Wal-Mart has emphasized that it would follow state law. But in a recent statement, the company said that any employee found to have lied on an application regarding a criminal past will be disqualified for the job.

"We actually get a lot of complaints and questions from those subject to background checks," said Beth Givens, director of the Privacy Rights Clearinghouse. "People are concerned that maybe a criminal conviction that has been expunged might be found and impact them. They are concerned that perhaps something they did in their youth could come up in the check."

In one instance reported to the Privacy Rights Clearinghouse, a 49-year-old engineer was fired from his job because a background check reported there was an outstanding warrant for his arrest. After he spent hours trying to find the source of the inaccurate information, he learned a background-check company had confused him with a much younger man with a similar name and of a different race.

The company refused to change its report and the court refused to change the file. The employee was not able to get his job back. The best this victim could do, according to Givens, was to obtain a letter, which he must carry with him to job searches, from the state attorney general saying there is no outstanding warrant for his arrest.

And he'll probably need that letter, no matter where he applies.

"Employers are risk-averse, so they don't want to hire someone who might cause them to be sued on down the line because of sexual harassment or identity fraud," Givens said. "I think employers are much more cautious than five years ago."

Join Amy Joyce from 11 a.m. to noon Tuesday at www.washingtonpost.com to discuss your life at work. You can e-mail her at lifeatwork@washpost.com.