Document ID: ./input/supremecourt_opinions/opinions/19pdf/18-587_5ifl.pdf
Page Number: 54.0

16 

DEPARTMENT OF HOMELAND SECURITY v. 
REGENTS OF UNIV. OF CAL. 

Opinion of THOMAS, J. 

surprising in light of our Constitution’s separation of pow-
ers.  No court can compel Executive Branch officials to ex-
ceed their congressionally delegated powers by continuing 
a program that was void ab initio.  Cf. Clinton v. City of New 
York, 524 U. S. 417 (1998); INS v. Chadha, 462 U. S. 919 
(1983); see also EPA v. EME Homer City Generation, L. P., 
572 U. S. 489, 542, n. 5 (2014) (Scalia, J., dissenting); Public 
Citizen v. Department of Justice, 491 U. S. 440, 487 (1989)
(Kennedy, J., concurring in judgment).  In reviewing agency
action, our role is to ensure that Executive Branch officials 
do not transgress the proper bounds of their authority, Ar-
lington, 569 U. S., at 327 (ROBERTS, C. J., dissenting), not 
to perpetuate a decision to unlawfully wield power in direct 
contravention  of  the  enabling  statute’s  clear  limits,  see 
UARG, 573 U. S., at 327–328; Barnhart v. Sigmon Coal Co., 
534 U. S. 438, 462 (2002).

Under our precedents, DHS can only exercise the author-
ity that Congress has chosen to delegate to it.  See UARG, 
573 U. S., at 327.  In implementing DACA, DHS under the
Obama administration arrogated to itself power it was not 
given by Congress.  Thus, every action taken by DHS under 
DACA is the unlawful exercise of power.  Now, under the 
Trump administration, DHS has provided the most compel-
ling  reason  to  rescind  DACA:  The  program  was  unlawful
and would force DHS to continue acting unlawfully if it car-
ried the program forward. 

III 
The majority’s demanding review of DHS’ decisionmak-
ing process is especially perverse given that the 2012 mem-
orandum flouted the APA’s procedural requirements—the
very  requirements  designed  to  prevent  arbitrary  deci-
sionmaking.  Even if DHS were authorized to create DACA, 
it  could  not  do  so  without  undertaking  an  administrative
rulemaking.  The fact that DHS did not engage in this pro-
cess  likely  provides  an  independent  basis  for  rescinding