Research Brief

Escalating auto insurance premiums have been a major public policy issue at the state level for the last three decades. No-fault auto insurance, spawned in the 1970s, was one response, offering cost savings to motorists and speedier compensation to auto accident victims. But because it required claimants to give up rights to seek compensation through the courts unless their losses exceeded a specified threshold, many states found it an unappealing alternative.

Choice auto insurance was proposed to address this concern. Under a choice auto insurance system, drivers may choose either a traditional auto insurance plan (tort) or a no-fault plan. Those who choose tort retain traditional tort rights and liabilities. Those who choose no-fault neither recover, nor are liable to others for, noneconomic losses (typically, pain and suffering) for less-serious injuries incurred in auto accidents.

Giving motorists a choice of coverage has strong appeal. But how does the choice alternative affect the premiums motorists pay? In a series of analyses, Stephen Carroll and Allan Abrahamse estimated how a choice auto insurance plan would affect insurance premiums in each state. Their basic finding: Overall, choice auto insurance could reduce the price tag for auto insurance by about 30 percent.


To understand the cost effects of choice auto insurance, the researchers estimated how a plan that offers a choice between tort and no-fault would affect the costs of auto insurance in each state that now relies on the traditional tort system. The plan they analyzed is absolute no-fault, the most extreme version of choice: Motorists may never sue, or be sued, for noneconomic loss. Thus, these estimates suggest the upper bound on the savings that can be accomplished in each tort state via the choice approach.

The researchers also estimated the cost effects of a choice plan in each state that already has some form of no-fault auto insurance. These estimates suggest the upper bound on the savings that can be accomplished in current no-fault states by extending the no-fault concept to its limit.

Results for Each State

In the tort states, the costs of compensating accident victims on behalf of drivers who elect no-fault would be at least 60 percent less than they would have been if those drivers had been insured under the traditional tort system. These savings include both the compensation paid to accident victims and the transactions costs incurred in providing that compensation.

If these savings are passed on to consumers, drivers in tort states who select choice could buy personal injury coverages for about 60 percent less than they pay for those coverages under the tort system. Because coverages for personal injury and property damage each account for roughly half of total auto insurance compensation costs, this 60 percent reduction translates roughly into a 30 percent reduction in a driver's total auto insurance premium. Premiums are unchanged for motorists who choose to remain in the traditional tort system.

In most no-fault states, a choice plan would have a similar effect on the costs of compensating accident victims and, again assuming that insurer savings are passed on to consumers, would result in similarly lower insurance premiums. And in most no-fault states, drivers who preferred to retain their current no-fault plan would pay no more for personal injury coverage than under the current system.

The savings an individual driver will realize from a choice system do not depend on the proportion of uninsured drivers in a state's current system, the proportion of previously insured who switch to absolute no-fault, or the proportion of the previously uninsured who switch to absolute no-fault. The effects of the plan on the total costs of auto insurance do depend on how many drivers choose to switch to the absolute no-fault option.

Nationwide, the reductions in personal injury premiums resulting from choice could be enormous. For example, if every currently insured driver in the country were to choose absolute no-fault, total auto insurance premiums in 1993—the last year for which data are available—would have been $26 billion lower. The table shows the relative savings for motorists in each state.

In addition to the savings in premiums, choice has another important cost effect. Because the no-fault premium is much lower than the premium for mandatory coverage under a tort system, some motorists who chose to drive without insurance under tort will choose no-fault. These uninsured drivers who switch to no-fault could contribute $1 billion to $4 billion to the compensation system nationwide.

This report is part of the RAND research brief series. RAND research briefs present policy-oriented summaries of individual published, peer-reviewed documents or of a body of published work.

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