During whose presidency were regulatory agencies often considered unconstitutional or invalid?

The assertion that regulatory agencies were often considered unconstitutional or invalid points primarily to the presidency of Franklin D. Roosevelt. During his administration, there was significant debate and legal scrutiny regarding the New Deal programs and the agencies established to implement them. The Supreme Court struck down several New Deal measures, asserting that certain agencies overstepped their constitutional boundaries, which raised concerns about the concentration of governmental power and the limits of federal authority.

Franklin D. Roosevelt's attempts to expand the role of the federal government in regulating the economy and providing social welfare led to a contentious relationship with the Supreme Court, culminating in efforts that included a controversial court-packing plan. This historical context illustrates the challenges faced by regulatory agencies during this era, highlighting a tension between innovation in governance and constitutional interpretation.