I have held off a few days replying on this thread to see how things would play out. I still feel there are posts that need answering, so here goes...
I absolutely agree with Dr Bill here. An instructor can only be expected to do so much.
Yes the instructor assumes a duty of care HOWEVER the instructor has a greater duty of care to their family! Your family has a right to expect that you will put their emotional, physical and financial needs ahead of the random student who winds up in your class.
You have no control over the issues that student brings as a result of their life experiences and choices. You have a responsibility to do your job to the highest legal and moral standard possible short of sacrificing your life and health. Just my .02
Am I reading it correctly that you would place your family's financial comfort above the life of a student? Really? I hope anyone with that mindset finds a different way to make a living.
A couple others have chimed in on both sides of the topic of an instructor's responsibility to assume risk. From my perspective, the instructor is responsible for providing 100% of the preparatory training an OW student requires. The instructor also makes the decisions about when and if a student is ready to enter the water, and when they are ready to advance to more difficult/risky skills and environments. The instructor makes those decisions for students who aren't ready to do it for themselves.
You have to believe that the student doesn't know the risks or how to manage them when they step through the classroom door. Anecdotal evidence tells us the student might believe the instructor is a "Dive God" who will keep them safe wherever they go. The student trusts that the instructor isn't going to put them in a situation that might cause them harm. If the instructor hasn't anticipated this and acted accordingly, who is responsible? Heck, reading posts here about the number of certified divers who will follow a DM into a situation beyond their skill level suggests that an instructor is remiss for assuming that a diver coming for an advanced class is prepared for it. If you're teaching an advanced class to a student whom you haven't previously taught or dived with, you had better not assume too much about their skills or knowledge. You can say that a diver showing up for AOW ought to have a mastery of everything related to the OW course, but that's just a cop-out. We all know that there are enough divers out there who don't have that mastery to make it a foreseeable issue. Assuming they do is a risk for their safety and yours, or at least your financial well-being.
With all that said, if you place someone in a situation where they are at risk, you absolutely have the moral obligation to assume that risk to get them out of it. What the criminal or civil law has to say about it, I couldn't tell you. I'd hope and expect the civil law to line up with moral responsibility and criminal law to be a bit more lax than that. Even then, the last thing I want from an instructor is for them to be thinking about legal issues when deciding how far to go toward saving a student in trouble. If you want to worry about your family's well-being, express that by ensuring that your students are ready to advance before allowing them to do so, and by keeping your students out of risky situations that they might not be able to handle.
Is the instructor in this circumstance responsible for this diver's death at any level? I neither know, nor do I want to go there. This is just a response to the generalizations that have been posted here.
As a side note, I would wager that there are quite a few divers who went below 60' as new divers with only OW certification. There are plenty who did "follow me" dives because there was a dive pro leading the way. I would also wager that quite a few of them would admit that it was a risky thing to do after more experience in the water and reading a few threads around here. Is 65' more dangerous than 55'? probably not to any significant degree. Is 100' more dangerous than 30'? Yeah, there's a lot more risk down there. Where does one draw the line? Better off to make it on the conservative side, and I couldn't argue with 60' as a reasonable number. If you don't like 60', where would you draw the line?
