I'm reminded of this *intensely* unethical science paper I read some twenty years or so where scientists electrocuted fish.
Why? To find out whether fish felt pain.
Their conclusion? They exhibit some behaviour patterns that suggest they could, but more research (i.e. electrocution) is required. You can't be sure, after all.
If this seems particularly disturbing, as if it's just some psychopaths using science as an excuse to live out their sicko fantasies ...