New research has found that partially automated vehicle systems do little if anything to prevent crashes.

The Insurance Institute for Highway Safety said a combination of crash data, insurance records, and its own studies of vehicles led it to conclude that the systems essentially amount to convenience features rather than safety ones.

The systems use cameras and sensors to propel a vehicle on the road and avoid other vehicles, but IIHS said they can’t handle many of the everyday traffic scenarios that people can, so drivers have to closely monitor progress in order to take over if needed. Yet the systems can lull drivers into a false sense of security, potentially reducing their attention on what’s taking place.

Following up on research it conducted in 2021, IIHS examined BMW and Nissan vehicles with the systems in a new study, finding that they don’t provide added safety on the road. Vehicles studied were 5 to 11 years old, and IIHS said it’s possible newer systems could be more effective, but it theorized that data already amassed for such technology already gives an accurate picture of its safety capabilities.

“At a minimum, safeguards like those IIHS promotes through its rating program are essential to reduce the risks that drivers will zone out or engage in other distracting activities while partial automation is switched on,” said IIHS Senior Vice President for Research Jessica Cicchino.

Over half of new vehicle models on the market last year came with partial automation as either standard or optional, the nonprofit group said. That’s despite the crashes that have happened while the systems were in use.

It distinguishes the partially automated features, which must be turned on and are typically used only on highways, from purely crash-avoidance features like automated emergency braking and lane-departure warnings, which activate only when danger arises.

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