BOSTON (CBS) – The I-Team has uncovered a story that affects hundreds of drivers who have paid hefty speeding fines over the past two years.

All of the tickets were written on a new road in Salem called the Bridge Street Bypass, a road Chester Chalipowski of Beverly knows well.

His familiarity with the road did not, however, prevent him from getting pulled over for speeding back in September. The officer told him he was doing 52 miles per hour in a 35-mile-per-hour zone and handed him a ticket for $170.

Chalipowski argued in court that the ticket was written illegally and he won.

Here’s why. According to state law, before a speed limit can be posted on a new road, state transportation officials have to conduct a traffic engineering study to determine what speed limit is most appropriate for the road.

The Massachusetts Department of Transportation website clearly states that any speed limits posted without a study are “illegal and unenforceable.”

Chalipowski did some digging and discovered that study was never done for the Bridge Street Bypass and that is the argument he made in Salem District Court before a judge and the officer that wrote him a ticket. The judge agreed and found him “not responsible.” Chalipowski was off the hook for the $170 ticket.

The I-Team wanted to find out how many other drivers got slapped with fines on that roadway. We obtained hundreds of pages of citations written by Salem police on that road. We found in 2010 and 2011, 896 drivers were fined a total of more than $175,000.

When we asked Salem police about it, they told us they are just enforcing signs posted by the state.

State Department of Transportation administrator Frank DePaola acknowledged to the I-Team that a mistake was made. He agreed that by the letter of the law, the tickets written during that time period are not legal. He also apologized to the hundreds of drivers who received tickets.

If you are one of those nearly 900 drivers, don’t expect a refund check in the mail. Like Chester Calippowski, you’ll have to fight your ticket in court.

That traffic engineering study was recently completed. That means if you are driving on the Bridget Street Bypass in Salem, slow down.