A Boxer dog is wearing a Cruising Companion car harness. They can be found at Bark Avenue in sizes XS-XL. Store is located at 7192 Kalanianaole Highway, #C-126. (Photo courtesy of Bark Avenue)
The pictures in the brochure below show what’s permitted and what isn’t. The Hawaii state law Section 291C-124 states that at any time, the pet cannot obstruct the driver, or be in the driver’s lap. The Honolulu Police Department (HPD) is tasked with enforcing this important law, designed to keep animals, passengers, drivers and others on the road safe.
Questions have come up if the animal can be loose in the back seat. We checked with The Hawaiian Humane Society. They work closely with the HPD and the answer is no. This is because unless the animal is safely strapped in, placed in a seperate section of the vechicle, or in a crate, there’s risk of obstruction to the driver and/or injury if hit by another vechicle. The same rationale for keeping a pet secured is why humans are secured while driving. 
As for animals in pick-up trucks, this is a city and county law. Sec. 15-24.22 states that “no dog or any other animal shall be transported on any public street or highway in any vehicle unless such animal is totally enclosed within such vehicle, within a secured container carried upon such vehicle, or securely cross-tethered to such vehicle in such a way as to prevent the animal from falling out of or off such vehicle, and to prevent injury to the animal.”
We hope this helps clears up some of the confusion. For additional clarification, please contact The Honolulu Police Department here.
