Funding the wall
The president's declaration of a national emergency in order to spur construction of a physical barrier along the southern border has roiled official Washington. Part of the funding the president says he will use comes from other funds already appropriated, but as yet unused. What does all this mean? Here's one overview, looking at military construction projects with unspent funds.
The Congressional Research Service has a broader view of how former President George Bush, using a national emergency declaration after 9/11, shifted $1.4 billion in defense construction spending to different purposes than Congress originally intended. According to this report, published in January:
According to DOD information, the department reported unobligated balances in the military construction and family housing accounts totaling $13.3 billion at the end of FY2018
That's a significant amount of money that could be shifted to wall construction -- if the president's emergency declaration survives both congressional and court challenges.
However, those challenges run up against existing federal law:
The use of Title 10 Section 2808 requires congressional notification. Subsection (b) states, “When a decision is made to undertake military construction projects authorized by this section, the Secretary of Defense shall notify ... the appropriate committees of Congress of the decision and of the estimated cost of the construction projects, including the cost of any real estate action pertaining to those construction projects.”
Nevertheless, according to DOD regulations the use of Section 2808 does not require a request to Congress for reprogramming (i.e., a change in the application of funds). The DOD Financial Management Regulation (FMR; DOD 7000.14-R), Paragraph 170303, Subsection (A), “Construction in the Event of a Declaration of War or National Emergency,” highlights additional guidance in DOD Directives (DODD) 3025.18 and 4270.5, the latter of which states reprogramming is not required for construction projects under 10 U.S.C. 2808.
That would appear to be a formidable barrier to any legal challenge. And it also undercuts a congressional challenge, which so far is largely partisan, and as yet, not substantial enough to overturn a presidential veto.