Why would a first aid kit be illegal? I guess I don't understand... I agree I could not stand asside and not act.
My kit is illegal is almost all states because I carry an epi-pen (epinephrine auto-injector) that I don't have a prescription for. I also carry hypodermic needles (prescription only or they're "drug paraphernalia") and a chest puncture syringe (a big needle for major pneumothorax cases). Technically you're supposed to be an EMT to possess chest seals in a few states.
I carry the hypo's not because I need the needles, but because it's almost impossible in my experience to get a syringe for wound irrigation (washing stuff out of a wound) that are STERILE and that don't come with a needle attached. Obviously I leave the needle on there because breaking the packaging to take it off would break the sterile package, making having the syringe useless to me.
On top of that I carry Rx meds for which I do have prescriptions (that is to say were prescribed to me at some point in time, clearly this Rx doesn't "allow" me to distribute them to others) these include oral antibiotics and painkillers as well as medical ointments (antibiotic mostly) as well as others that I obtained outside the United States but are not legal for sale in the United States, or require an Rx, which I don't have. Clindamycin (3% topical) being one of them. Clindamycin is an EXTREMELY effective antibiotic ointment because not only is it extremely wide-spectrum and extremely lethal to bacteria but it also adsorbs through the skin to kill bacteria that have already made their way well into a wound. It's only available in the United States by Rx, and even then only at 1% concentration.
If you ever want to see this demonstrated, wait til you or one of your kids has a huge pimple. Dab 1/4 of a pea size of 1% clindamycin on it, rub it in and wait 4-6 hours. Pimple is GONE. Like it was never there.
Many ask why I have this kit; because I do A LOT of backwoods (5-24+ hours from a hospital in a best case scenario) camping, hunting and fishing in some cases, especially if there's snow or a vehicle breaks down it could be a week or more.
In many of these cases there simply isn't medical attention available other than what I or my friends can provide, so I have to carry it with us whether it's strictly legal or not. If someone has a bone sticking out of their leg from a fall, it's generally up to us to administer first aid, treat for shock, start antibiotics etc and usually treat further or that person stands a very good chance of not surviving to make it to the hospital.
Unfortunately, the law simply doesn't understand or provide for such a scenario.
Understand this; I'm NOT ADVOCATING THAT YOU BREAK THE LAW in any way.
I'm merely pointing out that in many cases carrying a truly complete medical kit, short of an ambulance on your back, will break the law in many cases. [And stealing an ambulance and carrying it around most assuredly will break the law.]
Should you have the training/understanding to effectively use one, you might consider having such a kit. If you don't know how to use it, then it's nothing but a legal liability for you.
In my experience, life sometimes hangs by a thread. If you're prepared; you might just keep that thread from breaking. If that requires breaking some law, then for me, so be it. I'd like to see some prosecutor put me on trial for the crime of "saving/attempting to save a life".
But that's a risk I'm personally willing to take.