Make sure your hiring managers understand that customer preference should play no part in their hiring decisions. Applicants' race, age, sex or religion should always be ir-relevant.
Courts have said that discrimination is discrimination, even if your hiring managers try to push off their bias onto a third party, using excuses such as "Our customers feel more comfortable dealing with (white or younger or male) employees."
Basing hiring decisions on the prejudices of your customer base, even if you're in a service industry that depends on customer satisfaction, is a sure way to land in court. That's because such preferences are direct evidence of discrimination, which are impossible to defend against. Be on guard for managers' bias-tainted comments, such as, "That applicant reflects who our average customer looks like."
Recent case: Ralph Jones, an African-American, was a certified poker dealer at Mississippi casinos. Jones was at the top of his game, even dealing in the World Poker Open. After repeated applications, he was hired on a temporary basis at the Horseshoe Casino, but he never earned a permanent job.
Jones sued, alleging race discrimination. One key piece of evidence: A former employee testified that she heard the hiring manager say "These good old white boys don't want black people touching their cards." The court ordered a trial based on that evidence of race discrimination. (Jones v. Horseshoe Casino, No. 04-60924, 5th Cir., 2005)
Final tip: Remind hiring managers that you have no tolerance for unguarded comments at work; employees often remember (and take notes on) offhand comments, such as the "white boys" comment above.