Your driving record seems a legitimate risk for insurers toconsider when they price auto insurance. But your maritalstatus?

Yes, young men in red sports cars will pay more forcoverage than everyone else, but it’s hard to see how being awidow, or being divorced or separated, has much to do with the oddsyou’ll be in an accident.

Yet single, separated, and divorced people, and widows, oftenpay more for policies than married customers, according to anew study from the ConsumerFederation of America (CFA). In the study, when a husband died,the cost of state-mandated liability coverage for the widow rose byan average of 20 percent at four of six major insurers, thestudy found.

The consumer advocacy association collected quotes forstate-mandated minimum liability insurance from the websites of sixinsurers—State Farm, Farmers Insurance, Nationwide MutualInsurance, Liberty Mutual Insurance, Geico, and Progressive—in 10cities ranging from Baltimore to Portland, Ore. Among thesix, only State Farm didn't charge different rates based on maritalstatus, the report found.

Why should marital status factor into pricing? Goodquestion, says the CFA, which wants state regulators to take aharder look at whether it's fair to use marital status and certainother factors. The CFA's executive director, Stephen Brobeck, notedin a press release that single, separated, and divorced people tendto have lower incomes than married people and that therefore usingmarital status in pricing "tends to discriminate against low- andmoderate-income Americans."

Marital status is a legitimate factor in judging a person'srisk, says Loretta Worters, vice president of communications forthe Insurance InformationInstitute, a non-profit group supported by the insuranceindustry. Actuarial studies show that someone who is married isless likely to be in an accident than someone who is single, shesays: "It's not 'I'm not married and am being charged more.'There's a bigger picture that has to do with your driving habitsand how they affect you. It's about the accidents."

Typically, when people get married, they become more responsibleand more concerned about their health, Worters says, and theirincreased risk aversion shows in a driving record that includesfewer accidents and tickets.

The CFA said that pricing differences between single and marriedcouples persisted regardless of age and that a 2004 NationalInstitutes of Health study that the industry likes to cite isflawed. That study shows single people having higher driving injuryrates than married people, but the CFA says that it "was basedon data collected in New Zealand around 1990 involving only 138injuries, a substantial minority of which involved drivingmotorcycles. And the difference in injury rates was only about onepercentage point."

The CFA study found that four of the six major insurersdidn't charge higher prices for domestic partners than formarried couples, but that both Geico and Progressive often did incertain cities, citing Baltimore, Tampa, Louisville, Minneapolis,Denver, and Phoenix. Progressive also charged more in Houston, thestudy said.

Marital status is just one of many elements thatcan work their way into auto insurance pricing, and thatthe CFA has studied over the years. In 2013, it released a studyabout the impact of credit scores on auto insurance rates, sayingthat the use of credit scores by insurers discriminated againstlower-income drivers. It has also released a study looking atthe connection between auto insurance rates andeducation.

As with marital status, some insurers think credit scores arevaluable information and use it, and some don't use it or weigh itdifferently in pricing, says the Insurance Information Institute'sWorters. In general, insurers use all sorts of factors inpricing, and are always looking for data that will allow them toset more accurate prices for coverage.

Allstate wasn't included in the marital status survey because oftime constraints and a redesign of its website that the CFA saidmakes it more difficult to make price comparisons.

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