As automakers continue to develop self-driving cars, residents in Missouri and across the U.S. are envisioning a time when there will be no accidents at all on the roads. However, according to a study from the Insurance Institute for Highway Safety, this will be far from the case. Researchers claim that self-driving cars could prevent only around one-third of crashes stemming from driver error.

After analyzing over 5,000 crashes from the National Motor Vehicle Crash Causation Survey, researchers were able to put the driver-related errors behind them into five distinct categories. Out of these, only two would be eliminated by the advent of self-driving cars: sensing and perceiving errors, such as distracted driving, and errors due to incapacitation, like alcohol intoxication, drug impairment and falling asleep at the wheel.

Sensing and perceiving errors were the cause of 24% of the crashes studied, and incapacitation was the cause of 10%. Accounting for 40% of the crashes were planning and deciding errors, such as tailgating and driving too fast on wet roads, making these the most widespread factors. The other two categories were predicting errors and mistakes in execution and performance.

To prevent these three other types of errors, self-driving cars must do more than identify hazards that human drivers would miss. Advocates say automakers should put safety rather than speed or driver preferences first.

A motorist who causes a crash due to negligent driving may soon be facing a personal injury case. As for those who are seeking compensation, they may want legal assistance because auto insurance companies can be aggressive in denying payment. A lawyer could help a victim understand how their case stands in relation to the state’s negligence laws.