Two of the most prominent electric cars have missed out on the highest award given for vehicle safety by the influential IIHS: Top Safety Pick+.
Funded by the insurance industry, the IIHS—which operates independently of the federal government—says that neither the BMW i3 nor the Tesla Model S performed well enough in its barrage of instrumented and measured tests to earn its top award.
The i3 turned in a strong performance in the group's four main crash tests—small overlap front, moderate overlap front, side impact, and roof strength.
DON'T MISS: NHTSA closes Autopilot investigation
Where BMW's dedicated electric car came up short was in its head restraints, which the IIHS rates only as "Acceptable," due to their limited protection from whiplash in rear-impact tests.
The IIHS tested only the cloth-covered, manually-operated seats on the entry-level i3.
It also said that the car's headlights rank "Acceptable" and that its available collision avoidance tech is classified as "Advanced."
Tesla Model S in IIHS testing
Although the two shouldn't be compared directly given their size disparity, the Tesla Model S turned in a vastly different performance.
Despite changes made to its side curtain airbags, the Model S ranked only as "Acceptable" in the IIHS' demanding small overlap test.
It's this test that replicates a vehicle's impact with a tree or a utility pole, for instance.
READ THIS: Tesla Model 3 preview
Tesla recently implemented a production change to address the small overlap test and the IIHS says it plans to test the updated vehicle.
The IIHS also says that the Model S' LED reflector headlamps, both adaptive and standard, turned in a "Poor" performance, its lowest rating.
2014 Nissan Leaf - IIHS small front overlap crash test
Notably, since the Model S' automatic emergency braking system (packaged within AutoPilot) hasn't been activated on all models, the IIHS wasn't able to test its effectiveness.
The i3 and Model S aren't the first electric cars tested by the IIHS.
The Nissan Leaf has also been subjected to the Virginia-based non-profit's extensive testing; the design, now seven years old, received a "Poor" rating for the small overlap front test.
However, the IIHS says that the i3 and Model S won't require extensive modifications like the up-for-a-redesign Leaf does.
"There's no reason the most efficient vehicles can't also be among the safest," says David Zuby, IIHS executive vice president and chief research officer, in a statement released to the media.
CHECK OUT: 2017 BMW i3 REx detailed
"We hope Tesla and BMW will continue to refine the designs of their electric models to maximize driver protection and, especially in the case of Tesla, improve their headlights."