"Be sure not to confuse contractual and tort concepts of duty. There are different criteria for a court finding that a tort duty of care exists, as opposed to a contractual duty. You (or your heirs) couldn't sue me for breaching a "contract to be dive buddies." (At least not without some pretty darned bizarre facts.) You (or your heirs) could sue me for failing to act as a reasonably prudent dive buddy would act under the circumstances. That duty arose from our relationship, not strictly from a contractual agreement"...
Thank you for pointing that out.
"Virtually nothing in law is clear cut, so disputes about whether a certain act or omission is or is not the basis for liability keeps the court's open and lots of us attorneys employed."
And hence, I suspect, the continued interest in the topic on this forum.
While not questioning either Peter's pronouncements nor yours regarding the strictures of the law, the fact remains that (pardon me if this sounds "Clinton-esque") in my experience there is an extraordinarily large array of meanings attached to the word "relationship" in your quote above.
Certainly two individuals who have been diving together for a long time might easily be defined in this manner.
But in addition to 'insta-buddies' on charter boats, there are many circumstances on dive boats nationally (at least) where buddy "relationships" may be said to exist pre-dive only using the most tenuous and feeble definitions. Situations abound where a mob of divers follows one DM trailed by another, or where photographers scatter once underwater who never had any intentions of diving together to begin with.
I suspect that in a very large percentage of cases the word "relationship", with respect to dive buddies on charter boats, is nowhere near as clear cut as it may academically be defined. And as in the case with the example Peter quoted, while the underlying tenets may be clearly established, I suspect it will continue to be difficult to prove the facts regarding who did (or failed to do) what to whom and when, if there is only one surviving diver and no witnesses. Ultimately the wrongful death suit against Benedotti by the heirs of his dive buddy was dismissed, despite his relationship(s) with the deceased.
Be all that as it may, you were quite correct that the relationship between two declared dive buddies is different from that between two individuals casually pursuing more plebian pursuits together. As I stated earlier, I stand corrected.
(Yet one more reason for me to continue to dive solo, whenever not diving with long-established dive buddies!)
Dive safe,
Doc