SAN FRANCISCO (KCBS) – A couple in their 60s, headed home from the Valentine’s Day Tony Bennett show at City Hall, was kicked off a San Francisco Muni bus even though they had paid the fare.

The fare inspector threatened to call the police on Bill Keyworth and his wife Mary Lou because they hopped on a 49 Van Ness bus on Tuesday using senior citizen Clipper cards, but weren’t carrying any identification proving they were eligible for the 65-and-older discount.

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The fare inspector who got on a few stops later scanned both of their Clipper cards, then noticed Mary Lou was not carrying a purse. Mr. Keyworth said that’s when the trouble started.

“She looks 66, like she is,” he recounted with a self-conscious laugh.

But rules are rules. Keyworth said the inspector insisted they either get off the bus or tell their story to a police officer. The couple decided to disembark rather than get arrested, but the situation did not end there.

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The senior scofflaws waited for 20 minutes while the fare inspector, still holding their Clipper cards, called for a supervisor. During this time, the supervisor communicated nothing to the Keyworths.

In the end, they got their Clipper cards back without receiving either a citation or an explanation. And they got on another bus, their transfers still valid, and rode home ruffled but otherwise without incident.

As part of an interview with the San Francisco Examiner, a spokesman for the San Francisco Metropolitan Transportation Agency, which oversees Muni, said the fare inspector acted correctly. Senior citizens are required to carry identification and fare inspectors routinely ask veteran bus riders like the Keyworths whether they have a driver’s license.

The fine for not carrying ID and paying a discount Muni fare is $100.

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