One question I frequently get from job hunters is whether it's legal for employers to ask for Social Security numbers on applications.

Another common question is whether it's legal to ask for dates of birth.

Two employment law attorneys, Kim Jones at Husch Blackwell Sanders and Shelly Freeman at Lathrop & Gage's HROI subsidiary, assured me that both requests are legal.

While it's illegal to ask about disabilities on job applications, there's no ban on asking for a Social Security number or age.

Both bits of identifying information may be requested to expedite background checks, should the employer decide to pursue the candidate, or to confirm the candidate is of legal age to hold the job.

Authorities also note, though, that asking for applicants' ages on applications could make it more difficult for an employer to fight age discrimination suits, should rejected applicants pursue such claims.

Asking for this information upfront also is at odds with what security experts recommend. Privacy advocates say employers should request Social Security numbers only after they've culled the applicant field and are ready to do in-depth research into a handful of candidates.

Some states prohibit the mandatory transfer of individual Social Security numbers over the Internet if the site isn't secure or the data aren't encrypted. But such laws say nothing about hand-delivered, faxed or mailed applications.

It also should be noted that some employers are required, for Equal Employment Opportunity or federal contracting records, to keep track of the demographics of their applicants and hires.

Typically in those instances, applicants will be asked to fill out a separate voluntary self-identification form to get the affirmation action information, and employers are supposed to keep that information separate from the rest of the application.

Job hunters understandably remain nervous that their age, race or sex might be held against them. Basically, though, employers are asking them to "trust me on this."

Diane Stafford is the workplace and careers columnist at The Kansas City Star. Her "Your Job" blog at economy.kansascity.com includes daily posts about job-related issues of wide interest. Readers may write to her at: Kansas City Star, 1729 Grand Blvd., Kansas City, Mo. 64108-1413, or by e-mail at dstafford@kcstar.com.

(c) 2009, The Kansas City Star.

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