If the fisherman has made no efforts, and placed no structure to avoid killing dolphins?
Yes. Because they structured things in such a way that it will happen, so its part of the design of the system. Being a byproduct doesn’t make it any less intentional if there is no effort to alter the design.
The purpose of a system is what it does
If a fisherman is paid to catch fish, and a dolphin gets caught in the net and dies, is the fisherman’s purpose to kill dolphins?
If the fisherman has made no efforts, and placed no structure to avoid killing dolphins?
Yes. Because they structured things in such a way that it will happen, so its part of the design of the system. Being a byproduct doesn’t make it any less intentional if there is no effort to alter the design.
No, then it’s his porpoise.