For drivers who cross cracked and crumbling Massachusetts bridges the signs are just about as clear as you can get. No trucks, this Wellesley sign demands and on this Revere Bridge, this sign obviously means: No trucks.

No trucks? We don't think so.

Look at this one and this one and this one. Each truck is breaking the law and as a result breaking down state bridges. Our investigation found one out of ten Mass bridges are in such critical condition, this is Fitchburg, and in such need of repair, this is Weston

State officials had to post weight limits to prevent the massive and repeated pounding of big rigs.

Tom Broderick, Mass Highway Department "They're killing the bridge and the fact of the matter is, their truck does make a difference."

Experts know the loads, the vibrations, the stress can result in extensive and dangerous damage, sometimes causing bridges to be shut down. The state's goal is to keep the big rigs off the vulnerable roads.

Tom Broderick, Mass Highway Department "If they don't get caught, they're putting the public at risk."

But we found: there are too many trucks, too many bridges and not enough police officers. Watch.

Stationed here along the Revere Beach Parkway Bridge cops pulled over truck after truck

Massachusetts State Trooper "get him out of here…"

Each ignored the sign saying: stay off. When the cops left we came back and so did the trucks. Flat beds, dump trucks, box trucks, a car carrier and even one owned by the city of Revere.

Here's the route 99 bridge it's posted with specific weight restrictions.

This day the big rigs drive right into the sights of the waiting state troopers. They scoped out cargo sizes, checked licenses and actually weighed the trucks with portable scales.

Some trucks were fine. But time after time the scales proved the trucks were way too heavy.

Hank "Do you realize you're 25 tons overweight?"

Truck driver"No, I didn't know that."

Everyone had an excuse

Hank "You shouldn't have been on that bridge."

Truck Driver"I was just following traffic."

Everyone got a ticket.

Problem is: once law enforcement sets up shop truckers who might otherwise get snagged get warned by way of their CB radio and suddenly: the sting is stung.

Trooper Brian McAnally, MA State Police"The likelihood of being ticketed is slim to none. They've probably gone over that bridge a thousand times and never been cited."

And stats we obtained prove it of the thousands of trucks on Massachusetts roads fewer than 200 tickets were written over the past four years.

Hank"We saw you stop truck after truck today, how many got away?"

Trooper Brian McAnally, MA State Police"Oh, I cant begin to count."

And even when they do get caught, the $200 fines are just the cost of doing business

Hank "Are you gonna pay the fine?"

Truck driver"My boss is, yeah."

As a result the bridges you rely on may be at their breaking point–truckers gambling they'll be driving where a cop isn't–and as a result, gambling with your safety.

Trooper Brian McAnally, MA State Police"I don't want to see a bridge collapse in Massachusetts to have more of a focus on the problem."

Hank"But?"

Trooper Brian McAnally, MA State Police"It could happen, it could happen."

So why don't the local police departments help catch renegade trucks? We found only about a dozen Massachusetts communities can afford the equipment and training that's necessary and as a result, its open season on their bridges.

(Copyright 2007 Sunbeam Television. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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