Smaller cars tend to suffer more driver fatalities, while large trucks and SUVs are deadliest to other motorists.gettyEven with steady advancements in auto safety, from seatbelts, airbags and collision-absorbing designs to high-tech driver-assist systems, it seems the laws of physics still reign supreme.A just-released study by the industry-supported Insurance Institute for Highway Safety confirms the elemental mantra that a larger and heavier vehicle will afford a considerably greater degree of occupant protection in a crash than will a smaller and lighter one. What's more there's another old saw that's proven to be undeniable: speed kills.The data analysis shows that better than half of all vehicles responsible for the highest driver death rates recorded from 2021-2024 are either subcompact/compact models or high-performance muscle cars.AdvertisementAdvertisement"Even the safest small cars don't fare well in crashes with large pickups and heavy SUVs," says IIHS President David Harkey. "Powerful engines and marketing that attracts aggressive drivers is the issue for sports cars and muscle cars. They're dangerous mainly because of how they're driven."The car the IIHS found to be the most lethal in crashes is the subcompact Kia Rio, with a reported driver death rate of 170 per million registered vehicles, followed closely by the Nissan Versa at 164. Both cars have since been dropped from their respective automakers' U.S. lines.At the other end of the ledger, the IIHS' study uncovered no fewer than six models, all of them either big SUVs or pickup trucks, that recorded exactly zero driver deaths per million registered miles.Perhaps ironically, the study also determined that while the largest rides on the road tend to afford the greatest occupant protection in a crash, they're also the deadliest to those driving the other vehicle. One of the most mammoth models for sale in the U.S., the heavy-duty Ram 3500, accounted for the highest death rate among other drivers involved in a collision, at 204 per million registered miles.AdvertisementAdvertisementOne model – the full-size Dodge Charger muscle car – shows up among the top ten models in both most-lethal lists.The majority of models that the data shows to be the least deadly to the other drivers in a wreck are luxury SUVs, led by the BMW X3 at seven per million registered miles driven.The IIHS' analysis pegs the average motorist death rate from 2021-2004 at 37 per million registration years, while the other-driver death rate is 53. It's believed the higher other-driver death rate is higher because many of the vehicles involved were from prior model years that afford less in the way of crash protection.Both reports are based on vehicles from the 2023 model year (including older versions having equivalent designs and features), ganering at least 100,000 registered vehicle years or having accounted for 20 or more deaths during the study period as reported by the federal Fatality Analysis Reporting System (FARS).AdvertisementAdvertisementThe IIHS releases this information every three years, with driver death rates being used for comparison, since every accident involves a motorist, but not necessary passengers. While the Institute conducts extensive crash tests to determine how well models within each vehicle class will best protects its occupants in a collision, the FARS report is considered more of a real-world assessment, as it considers more than just how well the hardware holds up, including driver behavior.Since the FARS data includes driver age and gender, the IIHS' says the rates were adjusted to account for male drivers' having higher rates of accidents and the fact that older motorists, even those piloting luxury cars with the latest high-tech safety gear, tend to lose their lives in crashes more frequently than do younger drivers who frequently own smaller vehicles out of economic necessity."Size and power matter, as do vehicle crashworthiness and effective crash avoidance systems," Harkey explains. "But these results are also a reminder that a big part of how safe you are behind the wheel depends on how safely you drive."The full report, with complete lists of driver-death rates, can be found here.Models With The Highest Driver Death Rates 2021-2024Kia Rio (Subcompact car): 170 per million registered milesNissan Versa (Subcompact car): 164Chrysler 300 (full-size car): 132Dodge Charger HEMI (full-size muscle car): 127Dodge Challenger (full-size muscle car): 125Kia Forte (compact car): 120Chevrolet Malibu (midsize car): 116Hyundai Venue 2WD (subcompact SUV): 113Nissan Altima (midsize car): 105Nissan Maxima (midsize car): 105Models With The Lowest Driver Death Rates 2021-2024Audi Q7 4WD (large luxury SUV): 0 per million registered milesBMW X7 4WD (large luxury SUV): 0Chevrolet Tahoe 4WD (large SUV): 0Mercedes-Benz GLB-Class 4WD (compact luxury SUV): 0Mercedes-Benz GLE-Class 2WD (midsize luxury SUV): 0Toyota Tundra CrewMax 4WD (full-size pickup): 0Porsche Macan 4WD (midsize luxury SUV): 4BMW X5 4WD (midsize luxury SUV): 5Toyota RAV4 Prime 4WD (compact SUV): 5Volkswagen Atlas 2WD (midsize SUV): 5Models With The Highest Other-Driver Death Rates 2021-2024Ram 3500 Crew Cab Long Bed 4WD (heavy-duty pickup): 204 per million registered milesDodge Charger HEMI (full-size muscle car): 161Dodge Charger (full-size car): 136Chevrolet Silverado 3500 Crew Cab 4WD (heavy-duty pickup): 126Ram 1500 Classic Crew Cab Short Bed 4WD (full-size pickup): 124Ram 1500 QuadCab 2WD (full-size pickup): 113Ram 2500 QuadCab Short Bed 4WD (heavy-duty pickup): 113Chevrolet Silverado 2500 Crew Cab 4WD (heavy-duty pickup): 111Ram 2500 Crew Cab Long Bed 4WD (heavy-duty pickup): 102Cadillac XT5 2WD (midsize luxury SUV): 100Ram 1500 Crew Cab Short Bed 2WD (full-size pickup): 100Models With The Lowest Other-Driver Death Rates 2021-2024BMW X3 2WD (compact luxury SUV): 7 per million registered milesVolvo XC40 4WD (compact luxury SUV): 8Mercedes-Benz GLS-Class 4WD (full-size luxury SUV): 9BMW X7 4WD (large luxury SUV): 11Volkswagen Atlas 4WD (midsize SUV): 13Porsche Cayenne 4WD (midsize luxury SUV): 15Mazda CX-30 4WD (compact SUV): 18Acura MDX 4WD (midsize luxury SUV): 22Jeep Cherokee 4WD (midsize SUV): 22Land Rover Range Rover Velar (midsize luxury SUV): 22AdvertisementAdvertisementNote: 4WD refers to both four-wheel-drive and all-wheel-drive models. Source: Insurance Institute for Highway Safety.This article was originally published on Forbes.com