"At a time when we need transit systems getting every last dollar they can, it's amazing this scam exists," says Streetsblog deputy editor Matthew Roth.
Roth uncovered the problem and found you can actually travel farther than the distance you paid for.
"The problem is there's no incentive not to cheat the system unless you just have good ethics," says Roth.
ABC7 bought a Clipper card to test it out and sure enough, we covered more ground than we should have.
ABC7 asked transit authorities why this problem hasn't been fixed. John Goodwin at the Metropolitan Transportation Commission said, "I think we're done with this. I wish you well," and hung up the phone.
"I think MTC is not happy that this is getting as much attention as it is," says Roth.
MTC oversees the Clipper card, which allows you to use one card for several different transit systems, like Caltrain and BART. Officials say the flaw is actually there on purpose as a built-in convenience for confused or inexperienced travelers. They rely on the goodwill of people to pay their debts by adding more money to their Clipper card, but riders see it as something that needs to be addressed.
"Jiminy, I can't believe that BART is usually good about that kind of thing. Well, I guess not all that good," says Linda Mora from Millbrae.
"That's not good. Hopefully they'll fix their flaw," says Larry Risley from Sacramento.
At this point, there's no indication that officials plan to do anything about this free ride.
