One First: “The Trump administration’s Monday spending freeze is likely to provoke a crisis over the constitutionality of “impoundment”—one that the justices could well have to resolve *very* soon. The move was announced in a cryptic and thinly reasoned two-page memo that went out over the signature of Matthew J. Vaeth, the acting director of the White House Office of Management and Budget. And the consequences are potentially cataclysmic—for virtually all foreign aid (including the distribution of HIV drugs in poor countries); for medical and other scientific research in the United States; for tons of different pools of support for educational institutions; and for virtually every other entity that receives federal financial assistance. (The memo excludes funds paid directly to individuals, like Social Security or other benefits—although it offers no principled basis for the distinction.) The freeze purports to be temporary—and only “to the extent permissible” by law, whatever that means. Thus, the Vaeth memo directs all agencies that administer affected funds to submit detailed lists of projects suspended under the new order by February 10. Those agencies in turn must assign “responsibility and oversight” to tracking the federal spending to a senior political appointee, not a career official. But there is no guarantee that the spigot will be turned back on in two weeks; and in the interim, the withholding of so much money will almost certainly cause irreparable harm to at least some of the affected parties even if it’s fully restored at the end of the “pause.” Thus, even if this measure is a stopgap (and that’s debatable at best), it’s one that is likely to cause numerous crises all its own. Even as the Trump administration has embarked upon a flurry of controversial initiatives over the past week, I’ve been reluctant to swing at every pitch. But this action belongs in a category unto itself. In essence, the Trump administration is claiming the unilateral power to at least temporarily “impound” tens of billions of dollars of appropriated funds—in direct conflict with Congress’s constitutional power of the purse, and in even more flagrant violation of the Impoundment Control Act of 1974 (ICA)…”