Parking tickets can be the bane of any driver who inadvertently left their vehicle at a meter too long or innocently parked on a street tagged for cleaning.

It's an experience David Hegarty knows all too well. The San Francisco resident paid more than $1,000 for citations a year, and finally said enough was enough. He learned how to contest them and won. Now he's ready to help you.

Hegarty has developed a new app called Fixed that calculates your chances of getting out of a ticket that you feel you got unjustly.

"For most people, the price of a ticket is enough that it stings, but not enough to go through the pain of figuring out how to contest it," he said. "You grumble about it, but you don't fight it. That is what the city is banking on — that it's just below your threshold where you want to fight it and are happy enough to pay it. That is what we hope to change. We have to make it easy to fight your ticket and access the due process that you are entitled to."

Fixed is only available in San Francisco at present, but it will be rolled out to other U.S. cities over the next 18 months. The Twin Cities is near the top of the list, he said.

Hegarty says parking rules are not as black and white as they seem. A temporary "No Parking" sign might be on the street, but maybe it wasn't posted in the right place or it was hidden by a snowbank. Or perhaps it was not posted in the time prescribed or the wording didn't conform to statute.

"Laws get written at the state and city level over different sessions of government, and sometimes they contradict each other or build on top of one another," Hegarty said. "When you go looking for parking laws, it's very confusing for an attorney, let alone for the average person on the street."

Hegarty says tickets commonly contain errors, such as an incorrectly documented VIN number or license plate, or maybe a ticket was written on a Monday when street cleaning prohibited parking on a Tuesday.

That is where Hegarty and Fixed come in. Hegarty hires researchers to comb through parking regulations to look for inconsistencies and potential errors in tickets. That's fed into a database, which runs an algorithm to calculate the odds of having a ticket tossed out. If the chances are good, the app suggests evidence the violator will need prove his case and prompts him to take photos of that evidence. That might include pictures of the citation, the location of the car, where a sign was posted or not, and what it said.

That information is sent to Fixed, which then crafts a letter to the city contesting the citation on the violator's behalf. "With fingers crossed, you win," Hegarty said. "There are lots of errors in parking tickets."

It's free to use Fixed to contest the ticket. Hegarty only gets paid if the ticket gets canceled — he collects 25 percent of what the original fine was.

Last year Minneapolis Traffic Control wrote 193,137 tickets. St. Paul wrote 99,796 in 2012. If trends here are like San Francisco's, only 5 percent of tickets are ever contested. But of those, a third are voided.

Hegarty said Fixed can help municipalities collect on tickets that are legit.

"The main issue with parking tickets is that people don't pay them," he said. "If you give somebody the option to dispute a claim and they feel they were treated fairly and get resolution quickly, the city is more likely to get paid."

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