Document ID: ./input/supremecourt_opinions/opinions/21pdf/19-1392_6j37.pdf/19-1392_6j37.pdf
Page Number: 65

Cite as:  597 U. S. ____ (2022) 

57 

Opinion of the Court 

1 
Problems begin with the very concept of an “undue bur-
den.”  As Justice Scalia noted in his Casey partial dissent,
determining whether a burden is “due” or “undue” is “inher-
ently standardless.”  505 U. S., at 992; see also June Medi-
cal  Services  L.  L.  C.  v.  Russo,  591  U. S.  ___,  ___  (2020) 
(GORSUCH, J., dissenting) (slip op., at 17) (“[W]hether a bur-
den is deemed undue depends heavily on which factors the
judge  considers  and  how  much  weight  he  accords  each  of 
them” (internal quotation marks and alterations omitted)).
The Casey plurality tried to put meaning into the “undue
burden” test by setting out three subsidiary rules, but these
rules created their own problems.  The first rule is that “a 
provision of law is invalid, if its purpose or effect is to place 
a  substantial  obstacle  in  the  path  of  a  woman  seeking  an 
abortion before the fetus attains viability.”  505 U. S., at 878 
(emphasis added); see also id., at 877.  But whether a par-
ticular  obstacle  qualifies  as  “substantial”  is  often  open  to 
reasonable  debate.    In  the  sense  relevant  here,  “substan-
tial” means “of ample or considerable amount, quantity, or
size.”  Random  House  Webster’s  Unabridged  Dictionary
1897 (2d ed. 2001).  Huge burdens are plainly “substantial,”
and  trivial  ones  are  not,  but  in  between  these  extremes, 
there is a wide gray area. 

This ambiguity is a problem, and the second rule, which 
applies at all stages of a pregnancy, muddies things further.
It  states  that  measures  designed  “to  ensure  that  the 
woman’s  choice  is  informed”  are  constitutional  so  long  as
they do not impose “an undue burden on the right.”  Casey, 
505 U. S., at 878.  To the extent that this rule applies to pre-
viability  abortions,  it  overlaps  with  the  first  rule  and  ap-
pears to impose a different standard.  Consider a law that 
imposes an insubstantial obstacle but serves little purpose. 
As applied to a pre-viability abortion, would such a regula-
tion be constitutional on the ground that it does not impose 
a “substantial obstacle”?  Or would it be unconstitutional on