The Q:

You're probably used to providing one or two forms of identification whenever you write a check to a merchant, but it seems more and more businesses are asking credit card users to cough up some picture ID, too.

"If you refuse to show them your ID, they claim they will not sell to you," said Jon Smith of Baltimore.

"I believe under the Uniform Commercial Code, if they display a credit card symbol (such as a MasterCard or Visa) showing those forms of payment are accepted and do not have a posted sign saying they require IDs to use your credit card ... that they cannot refuse selling to you as you have abided by all of their posted policies and have presented a valid form of payment for a product or service."

The stores may try to pass off that practice as protecting consumers from fraud, but Smith says he believes businesses are just protecting their own behind. Are merchants allowed to ask for a photo ID when consumers use credit cards for payment, Smith wondered?

The A:

A signature on the back of the credit card is all the identification a consumer needs.

Regardless of whether a merchant posts an ID rule, card companies specifically ban practices requiring cardholders to show government identification to make a purchase.

Visa's merchant rules say:

Although Visa rules do not preclude merchants from asking for cardholder ID, merchants cannot make an ID a condition of acceptance. Therefore, merchants cannot refuse to complete a purchase transaction because a cardholder refuses to provide ID. Visa believes merchants should not ask for ID as part of their regular card acceptance procedures.

Here are MasterCard's rules:

A merchant must not refuse to complete a MasterCard card transaction solely because a cardholder who has complied with the conditions for presentment of a card at the POI [point of interaction] refuses to provide additional identification information, except as specifically permitted or required by the Standards. A merchant may require additional identification from the cardholder if the information is required to complete the transaction, such as for shipping purposes.

American Express and Discover have similar rules.

There are some exceptions to this rule. Merchants may ask to see ID if a card isn't signed. If you're paying by phone or on the Web, merchants may ask for identifying information such as address or ZIP code. In some cases, merchants may ask to see ID if you're making a down payment or if your purchase requires delivery.

While the request for ID may seem a legitimate way to protect the cardholder and the business, the prohibition on generally doing so is based on the idea that the card companies guarantee all purchases on cards that have been properly checked for signatures.

Simply put, when merchants agreed to the rules to accept those cards, they agreed to accept your card, too - no questions asked.

If a business demands your ID, you may refuse. But prepare for the business to refuse to do business with you. You should then notify the card company about the problem you had and name the business. Most card companies will investigate and either order the practice stopped or penalize the business for violating the merchant contract.

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