Buddy responsibility doesn't often make it into the court reporters. But here is one case from Washington state: Rasmussen v. Bendotti
http://caselaw.lp.findlaw.com/scripts/getcase.pl?court=wa&vol=2001_app/19464-7&invol=3
"To hold a defendant liable for negligence, the plaintiff must show that the defendant proximately caused the plaintiff's injury. Crowe v. Gaston, 134 Wn.2d 509, 514, 951 P.2d 1118 (1998). Proximate cause is generally a question of fact. Hertog v. City of Seattle, 138 Wn.2d 265, 275, 979 P.2d 400 (1999). Here, the trial court, sitting as the fact finder, found that any negligence on the part of Eugene Bendotti was "too attenuated" from Bonny Jo Bendotti's death to hold Gene legally liable. Gene was Bonny's scuba diving buddy. He failed to properly attach a power inflator to his buoyancy compensator. This required an emergency ascent. Bonny then drowned after her equipment became entangled in a rope. We conclude that the trial court's finding is adequately supported by the evidence, and affirm the judgment dismissing Cully, Adam, and Brandy Jo Rasmussen's wrongful death suit."
Reading further into it, the appeals court simply accepted the trial court's conclusion that buddying up does create a duty of care. They even accepted that Gene's failure to attach his power inflator (and catch it in a pre-dive check) was negligence. And they refused to grant him an exception to his duty to care based on his emergency ascent (since the ascent was a result of his negligence).
But you know what? They still tossed the thing out. Why? Proving negligence is not enough. The plaintiff also has to prove that the injury would not have occurred even if the defendant had not acted negligently.
"Here, the question simply put is if Gene had properly connected his power inflator would Bonny be alive today? The court held that the connection between Gene's breach and Bonny's death was too attenuated to say that had he connected his power inflator she would still be alive. The evidence amply supports this fact.
Jon Hardy, a scuba diving expert, testified that there was no connection between Gene's failure to attach his power inflator and Bonny's subsequent entanglement. Nor did he believe there was a connection between the loss of buddy contact and Bonny's death. He further stated that he believed the proximate cause of Bonny's death was her failure to carry a dive knife.
How Bonny became entangled and why she was not able to free herself is not known. Also unknown is whether Gene could have saved her in any event. So, whether Gene could have saved her is speculation. And speculation is not sufficient to establish proximate cause."
The upshot of all this is.... act anywhere near reasonably and you'll be fine. Did you really expect anything else? Still, the duty to care is real (in Washington state anyway), so if you have reservations about an insta-buddy, you do have a reasonable legal argument for refusing the pairing.
