Regulating is an inherently legislative exercise, in that it entails the promulgation of rules that control private behavior. Indeed, most policy now is rendered via regulation, thanks to the geometric growth of the executive branch during the post-war years.*
However, unlike legislators in congress, executive agency bureaucrats are unaccountable to the electorate. As a result, there’s a danger that executive agencies are effectuating policy absent a popular mandate and away from the public eye.