Document ID: ./input/supremecourt_opinions/opinions/19pdf/17-1618_hfci.pdf
Page Number: 76

Cite as:  590 U. S. ____ (2020) 

39 

ALITO, J., dissenting 

conduct is not sex discrimination, the statute does not ap-
ply.  Thus, this lesson simply takes us back to the question
whether  discrimination  because  of  sexual  orientation  or 
gender identity is a form of discrimination because of bio-
logical  sex.    For  reasons  already  discussed,  see  Part  I–A, 
supra, it is not. 

It likewise proves nothing of relevance here to note that 
an  employer  cannot  escape  liability  by  showing  that  dis-
crimination on a prohibited ground was not its sole motiva-
tion.  So long as a prohibited ground was a motivating fac-
tor, the existence of other motivating factors does not defeat
liability.

The Court makes much of the argument that “[i]n Phil-
lips, the employer could have accurately spoken of its policy 
as one based on ‘motherhood.’ ”  Ante, at 14; see also ante, 
at 16.  But motherhood, by definition, is a condition that can 
be  experienced  only  by  women,  so  a  policy  that  distin-
guishes between motherhood and parenthood is necessarily
a policy that draws a sex-based distinction.  There was sex 
discrimination  in  Phillips,  because  women  with  children 
were  treated  disadvantageously  compared  to  men  with
children. 

Lesson number two—“the plaintiff ’s sex need not be the
sole  or  primary  cause  of  the  employer’s  adverse  action,” 
ante, at 14—is similarly unhelpful.  The standard of causa-
tion in these cases is whether sex is necessarily a “motivat-
ing factor” when an employer discriminates on the basis of 
sexual orientation or gender identity.  42 U. S. C. §2000e– 
2(m).  But the essential question—whether discrimination
because of sexual orientation or gender identity constitutes
sex discrimination—would be the same no matter what cau-
sation standard applied.  The Court’s extensive discussion 
of causation standards is so much smoke. 

Lesson  number  three––“an  employer  cannot  escape  lia-
bility  by  demonstrating  that  it  treats  males  and  females 
comparably as groups,” ante, at 15, is also irrelevant.  There