The GAO says Chad Wolf and Ken Cuccinelli are in their positions illegally

This should provide some explosives.

The Vacancies Reform Act permits certain individuals to serve as acting officials in vacant presidentially appointed, Senate confirmed positions (PAS) for limited periods of time. 5 U.S.C. §§ 3345, 3346. The Vacancies Reform Act is generally the exclusive means for filling a vacancy in a PAS position unless another statute provides an exception.2 Pursuant to the Vacancies Reform Act, the first assistant to a PAS position automatically becomes the acting official in case of a vacancy unless the President designates another individual who meets the Vacancies Reform Act’s eligibility requirements.

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Upon Secretary Kirstjen Nielsen’s resignation on April 10, 2019, the official who assumed the title of Acting Secretary [Kevin McAleenan] had not been designated in the order of succession to serve upon the Secretary’s resignation.

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Mr. McAleenan did not have the authority to amend the Secretary’s existing designation.

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Because the incorrect official assumed the title of Acting Secretary at that time, subsequent amendments to the order of succession made by that official were invalid and officials who assumed their positions under such amendments [...] were named by reference to an invalid order of succession.

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[U]pon the resignation of Secretary Kirstjen Nielsen, the express terms of the then existing designation required the Director of the Cybersecurity and Infrastructure Security Agency (CISA) to assume that title instead of the Commissioner of Customs and Border Protection (CBP), Kevin McAleenan. As such, the subsequent appointments of Under Secretary for Strategy, Policy, and Plans, Chad Wolf and Principal Deputy Director of U.S. Citizenship and Immigration Services (USCIS) Ken Cuccinelli were also improper because they relied on an amended designation made by Mr. McAleenan.

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We have not reviewed the legality of other actions taken by these officials; we are referring the matter to the Inspector General of DHS for review.

  Government Accountability Office

Let the fireworks begin.