If Climate Villains were unlikely to counterfactually receive any representation, then the case for representing them might be stronger. But in reality, these are some of the best capitalized and politically powerful actors on the planet. They don’t need our help, and will be able to find good lawyers regardless.
I actually think there is a good market based moral case for each individual to not represent them, especially if this becomes a widespread issue. This is because even if there is a pro tanto duty to ensure they are represented, there is no duty to ensure they are represented cheaply. If few lawyers are willing to defend them, the price for this will increase and they will be less inclined to pursue actions that will increase the likelihood of lawsuits. Second, the quantity and quality of lawyers they and other bad actors can hire will eventually decline, or at least the price will rise significantly, making it less likely that they can successfully pursue typical corporate tactics like overwhelming the other party with near-spurious claims and appealing indefinitely.
I actually think there is a good market based moral case for each individual to not represent them, especially if this becomes a widespread issue. This is because even if there is a pro tanto duty to ensure they are represented, there is no duty to ensure they are represented cheaply. If few lawyers are willing to defend them, the price for this will increase and they will be less inclined to pursue actions that will increase the likelihood of lawsuits. Second, the quantity and quality of lawyers they and other bad actors can hire will eventually decline, or at least the price will rise significantly, making it less likely that they can successfully pursue typical corporate tactics like overwhelming the other party with near-spurious claims and appealing indefinitely.