In this Essay, Professor Cross responds to recent academic efforts to develop a robust judicial federalism doctrine, which advocate increased judicial review of legislative activities and suggest that an expanded federalism doctrine would have significant, negative consequences. Professor Cross challenges the assumption that courts would apply a principled, neutral doctrine of federalism, using empirical evidence to demonstrate that courts consistently have invoked federalism for political or ideological reasons. He suggests that the flexibility of the proposed federalism doctrines would allow judges to manipulate results to achieve ideological ends and that the resulting intrusive judicial review would implicate separation of powers concerns and impair legislative functioning. He argues further that institutional realities-the susceptibility of judges to the concerns and influence of the other branches of government-would prevent such federalism from being a meaningful restriction on the powers of the federal government in any event. Professor Cross concludes that proponents of expanded federalism should focus their efforts on creating a practicable doctrine that is not as vulnerable to ready manipulation and high systemic costs.