Anyone live local to them that could contact the police about her driving - if she's having to either hold his head with one or constantly check to make sure his head hasn't fallen over - then she is driving distracted and she could end up killing him or worse - some innocent person
In short, ain't happenin'.
The tl;dr version:
The police would have to observe Hannah driving and pull her over for an unrelated issue like speeding, running a stop sign, exhibiting significant road rage that's endangering other drivers (my money's on that one), or something as simple as a burned out taillight. And in MN, she could be pulled over for anyone in the vehicle not being properly restrained.
dps.mn.gov
During a traffic stop an officer would have to question them if/how Shane is strapped in. Or, heaven forbid, they respond to the scene of an accident and have to pull what's left of Shane (or both of them) from the wreckage. That fall off the icy ramp when Shane said he saw his life flash before his eyes is nothing compared to the damage a MVA could do. Flip that big SUV just once, and it would be a miracle if he survived. If his neck didn't snap first, and the vehicle landed upside down, the roof could be compromised enough for his 400-pound wheelchair to crush him which, ironically, is the reason commercial airlines claim they do not allow wheelchair users to remain in their wheelchairs in the cabin.
You would have thought his parents would have insisted upon proper restraints when they were still providing his care, but I remember in one of the early videos seeing his mother reach over and prop his head back up. The laws vary from U.S. state to U.S. state, but PA laws are similar to MN's.
Most states place responsibility on the DRIVER for all passengers being properly belted in. So what that means is I don't care if my front-seat passenger (or a minor in the back in my state) doesn't want to buckle up. I'm not going to risk getting a traffic ticket because YOU don't like wearing a seatbelt.
Shane had one of those foam neck braces in an early video but said he hated wearing it. Same as with his wrist splints (and perhaps other sorts of splints that might have helped him have more mobility and less deformity today) had his parents, and once he became an adult, Shane, had the discipline to use such aids. When he was a minor they could have insisted he wear the splints prescribed. What was he going to do? Tear them off?
Other than providing minimal support, such as keeping his head from falling over when they hit a pothole or speed bump or turn a corner (seems it would be more comfortable), that foam neck brace isn't going to provide nearly the level of support a rigid neck brace or toddler seat would. Even his "airplane seat" strapped into the back seat wouldn't keep his head from falling forward, but it looks safer than him sitting up front, his head sitting precariously atop his neck like Colorado Springs' "Balanced Rock."
It still seems like he needs a system to keep his neck completely stable in all directions. I can see why he'd probably hate it, but it could mean the difference between life and death in a just minor accident.
The police aren't going to knock on their door and say, "Mr. Burcaw, we've received information regarding your well-being which necessitates we check the safety equipment required for you to ride in a passenger vehicle," any more than if you report your neighbors who regularly let their unrestrained toddlers climb all over the inside of their moving car... ain't gonna happen. The police would have to witness the vehicle moving and see the kids bouncing around inside. I suppose a police officer could pull up beside S&G at a traffic light, look over, and think Shane is a small child who should be riding in a proper seat in the back and pull them over for that, but that's a long shot. He may have gotten a medical exception (from a not-very-bright doctor IMO), so that would be the end of it. They have to have a reason to stop someone besides the word of someone, however well-meaning the person is.
As others have noted and Hannah's frequent distracted driving shows, his wheelchair straps don't do anything to stabilize his neck. Even a sudden stop or low-speed impact could snap his neck in half like a twig. At the very minimum it would seem if he's going to ride in his chair up front that there needs to be a rigid neck brace (something much sturdier than his horseshoe pillow) and some sort of strap(s) to secure his forehead to his headrest... assuming the headrest on his wheelchair could withstand the force the headrest of the OEM seatback could. It looks pretty flimsy.
I think others have mentioned the risk of someone of his size being hit with an airbag. Even very short adults are at risk of serious injury from a deployed airbag.
Since he's the height of a toddler with even less muscle than a toddler, it stands to reason that, based upon his height and size that he should be strapped into at a minimum a toddler seat, depending on the local and MN state laws.
I'm not an M.D., but I do have an biomedical engineering degree, so I have had some experience in designing medical equipment. Also, a very good understanding of physics! It's horrifying to consider all the physics involved in all the scenarios previously discussed. I don't know who began this particular topic, but thank you. I hadn't really considered just how dangerous it seems for Shane to ride in a motor vehicle sitting in his wheelchair. I rarely read the comments on their videos, but has anyone seen someone ask them about this subject?