I attended an identity-theft seminar in which a Washington State Patrol officer suggested that consumers not sign the back of their credit cards and instead write: "See photo ID." Should I sign my cards this way or not?

— J.S., Seattle

A: Some experts and law-enforcement agencies, including the State Patrol, recommend signing your credit cards like this as an additional level of security in combating credit-card fraud.

But some credit-card issuers and financial institutions say this is contrary to their rules requiring a valid signature in that space.

Detective David Startup said he's never heard of a consumer having a credit card rejected when it is marked with this phrase in place of a signature. Startup is one of two detectives in an identity-theft unit created by the State Patrol and the State Department of Licensing.

It forces the retail clerk to ask for a driver's license or other identification and compare both the signature and the photo there with the signature on the credit-card slip. "It's just an extra measure that the clerk needs to take to verify that's the person who's in front of them," said Startup.

However, a Visa USA spokesman said the company "does not accept 'see ID' as a valid substitute for a signature." Leaving it blank hinders the merchant's ability to compare signatures, he said.

Your best bet: Do both, said Melissa Wolff, loss-prevention and compliance manager for the Washington State Employees Credit Union. It is OK for cardholders to squeeze both their signatures and the "see photo ID" phrase onto the back of the card, she said.

Jolayne Houtz, Times staff reporter

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