We have to thank WCBS 2 for reminding us of what we know already: sometimes when you swipe your Metrocard and it says "Swipe Again At This Turnstile," it has already deducted a fare, though the turnstile will not let you through. And that hurts, especially after turnstile groin and/or torso injuries. Not to mention the fact that they just took your money.
According to the news report, the MTA apparently does not even bother denying this, claiming that its poor, 12-year old turnstiles sometimes can't read the magnetic stripe and the "swipe again" message means "a fare may or may not have been deducted." Funny how it never seems to work in your favor, does it? And funny how the reader works well enough to deduct the fare from the card, but not well enough to open the turnstile for you.
City Comptroller candidate John Liu wins some brownie points on this issue, stating the obvious, "The MetroCard system has been less than reliable for a long time," being part of a general system of an "MTA unaccountable for their overall finances."
Official MTA policy is that if you feel that you have been charged in error, you should bring the metrocard to the attention of a token booth clerk, though of course there are no guarantees, and often you don't realize you have been charged. You get the sense that the MTA is big enough to get away with it, and that's about all.