In recent months, at least one major company has been changing its whole philosophy of how rates are set. And it's not so much how well you drive, but how well you pay your bills.

News Specialist Jed Boal has been investigating, and has an eye-opening report called "Highway Robbery."

Over the years, there's been an agreement between the insurance companies and us--the insured. They've calculated our premiums based on age, driving records and the cars we drive.

But a new practice could make your rates skyrocket and force you off the road.

Out on the roads, we have to stay alert for unforseen hazards.

One woman was blindsided by a bad experience with her insurance company of 20 years.

Emergency medical costs snowballed last year.

She's on a fixed income. When she renewed her car insurance this year, her premium jumped 60-percent.

Jane/Insurance Customer: IT BLEW ME AWAY. SO I CALL, AND HE DIDN'T HAVE ANY IDEA WHAT WAS GOING ON.

Her agent had no answers.

Jane/Insurance Customer: I HAVE A CLEAN DRIVING RECORD. I HAVE NO TICKETS. I HAVE NOTHING.

Later, the company sent her a letter explaining they had evaluated her insurance based not only on her driving record, but also on her credit.

Jane/Insurance Customer: WHAT ASSOCIATION DOES MY CREDIT HAVE TO DO WITH THE INSURANCE?

She could not pay the high premium and switched companies. And she's not alone.

One Farmer's Insurance agent, who agreed to talk to us if we kept his identity confidential, said it happened to dozens of his clients.

Farmer's Agent: I DEFINITELY WILL SAY IT'S UNFAIR.

Beginning January 1st, he says the company started to use a score based on your credit report to calculate premiums. It's known as a FARA score.

The score has nothing to do with your driving record or age. The rates are graduated. The worse your credit, the higher your rate.

Farmer's Agent: IT SEEMS TO ME THE INSURANCE INDUSTRY HAS SAID 'WE WILL TREAT PEOPLE EQUALLY.' AND IN MY OPINION THEY'RE NOT TREATING THEM EQUALLY, THEY'RE TREATING SOME OF THEM VERY UNFAIRLY.

One client had no tickets and no accidents. He paid Farmers $477 every six months. In January it went to $657. The agent had to deliver the bad news.

Farmer's Agent: THAT'S A PRETTY HARD THING TO DO WHEN YOU'RE AN INSURANCE AGENT, WHEN NO ONE'S HAD A CHANGE OF CIRCUMSTANCES, TO EXPLAIN AWAY A $200 INCREASE.

Jed Boal/Eyewitness News: THIS PRACTICE IS NOT ILLEGAL, BUT IS IT FAIR TO YOU? THE STATE INSURANCE COMMISSION SAYS THAT THIS ISSUE IS SIMMERING, AND IT WILL EXAMINE THE PROBLEM AND DETERMINE WHETHER IT NEEDS TO STEP IN AND REGULATE.

Brad Tibbitts/Utah Property & Casualty Insurance Division: WE HAVE HEARD OF SITUATIONS THAT ARE VERY EXTREME, ALL THE WAY DOWN TO SOMEONE WHO HAD AN INCREASE OF 20-30 BUCKS A MONTH BASED ON THEIR CREDIT SCORING.

Brad Tibbets with the Utah Insurance Department says the score was developed to determine whether a person is a good or a bad risk.

He says most Utah insurance companies use FARA scores. How they use them varies.

He says companies have abused the practice--motorists have been dropped at renewal.

Farmers filed with the state to use FARA scoring.

If companies use credit as a component to set rates,that's fine. If it's the sole factor, the state may step in.

But here's a problem-- credit reports are not always accurate. The state wants to make sure the rating is fair. But consumers need to ask questions when they're shopping for insurance.

Brad Tibbitts/Property & Casualty Insurance Division: THEY REALLY NEED TO BE AWARE OF IT. THERE'S A LOT OF PEOPLE OUT THERE WHO ARE NOT HAPPY ABOUT IT. BUT, IT'S KIND OF A FACT OF LIFE.

The State Director of Farmer's Insurance says he cannot comment on specific policies. But he defends the use of the FARA scores.

He says many customers are rewarded with lower rates because of good scores, and he says Farmer's does not terminate insurance based on the scores.