There are many public policy and law questions that benefit from positioning respondents in contrasting or even adversarial positions, for example taking a pro or con position on a question. Case law obviously comes to mind and it's one of the reasons dissenting views and opinions are published. They have merit in their own right even though they are minority views. Even for non law related questions, most of the serious ones that had depth to them were argued from multiple points of view.
To give an example, if I posed the question is there a right to privacy in the Constitution after Roe vs Wade, all merry hell would break loose on this site. To understand this particular question correctly it's really necessary to give both sides of the argument a fair shake as they will start off at a similar point but end up in vastly different spots.
I would therefore like an adversarial question feature that would enable upvoting and responses for both "pro" or "con" responses that would promote looking at two or more sides of complicated issues.