Fiscal responsibility means limiting government expenditures to programs that can be convincingly said to generate benefits in excess of their costs. This does not rule out programs with large expenditures, or ones whose benefits are difficult to quantify; national defense is guilty on both counts, yet few believe that substantial military expenditure is necessarily irresponsible.
Any significant expenditure, however, should come with a credible claim that it produces a benefit large enough to outweigh both the expenditure itself and any ancillary costs. From this perspective, drug prohibition is not remotely consistent with fiscal responsibility. This policy costs the public purse around $70 billion per year, according to my estimates, yet no evidence suggests that prohibition reduces drug use to a significant degree.
And prohibition has unintended consequences that push its cost‐benefit ratio even farther in the wrong direction. Prohibition generates violence and corruption by pushing drug markets underground and inflating prices. Prohibition inhibits quality control, so users suffer accidental poisoning and overdoses. Prohibition destroys civil liberties, inhibits legitimate medical uses of targeted drugs, and wreaks havoc in drug‐producing countries.
Drug prohibition, at least when imposed at the federal level, is also hard to reconcile with constitutionally limited government. The Constitution gives the federal government a few expressly enumerated powers, with all others reserved to the states (or to the people) under the Tenth Amendment. None of the enumerated powers authorizes Congress to outlaw specific products, only to regulate interstate commerce. Thus laws regulating interstate trade in drugs might pass constitutional muster, but outright bans cannot. Indeed, when the United States wanted to outlaw alcohol, it amended the Constitution itself to do so. The country has never adopted such a constitutional authorization for drug prohibition.
Finally, drug prohibition is hopelessly inconsistent with allegiance to free markets, regardless of the level of government. Free markets should mean both that businesses can operate as they please and that individuals can purchase and consume whatever they want, so long as these actions do not harm others, even when such decisions seem unwise. Drug prohibition interferes with precisely these activities.
Thus, if the tea‐party believes in its principles, it must choose the libertarian path on drug prohibition.