Document ID: ./input/supremecourt_opinions/opinions/22pdf/21-1449_d9eh.pdf
Page Number: 6.0

Cite as:  598 U. S. ____ (2023) 

3 

Opinion of the Court 

preempts state law even when the two only arguably con-
flict.  San Diego Building Trades Council v.  Garmon, 359 
U. S. 236, 245 (1959) (“When an activity is arguably subject 
to §7 or §8 of the [NLRA], the States as well as the federal
courts  must  defer  to  the  exclusive  competence  of  the  Na-
tional Labor Relations Board”).  This doctrine—named Gar-
mon preemption after the case that originated it—thus goes 
beyond the usual preemption rule.  Under Garmon, States 
cannot regulate conduct “that the NLRA protects, prohibits, 
or  arguably  protects  or  prohibits.”  Wisconsin  Dept.  of  In-
dustry v. Gould Inc., 475 U. S. 282, 286 (1986). 

Though broad, this standard has teeth.  Longshoremen v. 
Davis, 476 U. S. 380, 394 (1986) (“The precondition for pre-
emption, that the conduct be ‘arguably’ protected or prohib-
ited, is not without substance”).  It requires more than “a
conclusory assertion” that the NLRA arguably protects or 
prohibits conduct.  Ibid.  “[A] party asserting pre-emption 
must advance an interpretation of the [NLRA] that is not
plainly contrary to its language and that has not been ‘au-
thoritatively rejected’ by the courts or the Board.”  Id., at 
395.  The  party  must  then  “put  forth  enough  evidence  to 
enable the court to find that the Board reasonably could up-
hold a claim based on such an interpretation.”  Ibid. 

If the court determines that the party has met its burden
to show that “there is an arguable case for pre-emption,” it
generally  must  grant  the  party’s  preemption  defense  and 
await the Board’s resolution of the legal status of the rele-
vant  conduct.    Id.,  at 397.1    After that,  “only  if  the  Board 
—————— 

1 We  have  recognized  exceptions  to  this  rule.    One  allows  a  court  to 
resolve a claim if the party raising it lacks a “reasonable opportunity” to 
secure a Board decision on the legal status of the conduct at issue.  Sears, 
Roebuck & Co. v. Carpenters, 436 U. S. 180, 201 (1978); see also Davis, 
476 U. S., at 393, n. 10.  Another applies if the conduct in question is “a 
merely  peripheral  concern”  of  the  NLRA.    San  Diego  Building  Trades 
Council v. Garmon, 359 U. S. 236, 243 (1959).  A third covers situations