Document ID: ./input/supremecourt_opinions/opinions/10pdf/09-152.pdf
Page Number: 32

Cite as:  562 U. S. ____ (2011) 

3 

SOTOMAYOR, J., dissenting 

§22(b)(1)  applies only where  neither  kind  of  defect  is  pre-
sent.  Because §22(b)(1) is invoked by vaccine manufactur-
ers  as  a  defense  to  tort  liability,  it  follows  that  the  “even
though”  clause  requires  a  vaccine  manufacturer  in  each 
civil  action  to  demonstrate  that  its  vaccine  is  free  from 
manufacturing  and  labeling  defects  to  fall  within  the 
liability exemption of §22(b)(1).2 

Given  that  the  “even  though”  clause  requires  the  ab-
sence  of  manufacturing  and  labeling  defects,  the  “if ” 
clause’s  reference  to  “side  effects  that  were  unavoidable” 
must refer to side effects caused by something other than
manufacturing  and  labeling  defects.    The  only  remaining
kind  of  product  defect  recognized  under  traditional  prod-
ucts  liability  law  is  a  design  defect.    Thus,  “side  effects 
that were unavoidable” must refer to side effects caused by
a  vaccine’s  design  that  were  “unavoidable.”  Because 
§22(b)(1) uses the conditional term “if,” moreover, the text
plainly  implies  that  some  side  effects  stemming  from  a
vaccine’s design are “unavoidable,” while others are avoid-
able.  See  Webster’s  Third  New  International  Dictionary 
1124 (2002) (“if ” means “in the event that,” “so long as,” or
“on  condition  that”).  Accordingly,  because  the  “if ”  clause 
(like  the  “even  though”  clause)  sets  forth  a  condition  to 
invoke  §22(b)(1)’s  defense  to  tort  liability,  Congress  must 
also have intended a vaccine manufacturer to demonstrate 
in  each  civil  action  that  the  particular  side  effects  of  a
vaccine’s design were “unavoidable.” 

Congress’  use  of  conditional  “if”  clauses  in  two  other 
provisions of the Vaccine Act supports the conclusion that
§22(b)(1)  requires  an  inquiry  in  each  case  in  which  a 
manufacturer  seeks  to  invoke  the  provision’s  exception  to 
—————— 

2 See Silkwood v. Kerr-McGee Corp., 464 U. S. 238, 255 (1984); Brown 
v.  Earthboard  Sports  USA,  Inc.,  481  F. 3d  901,  912  (CA6  2007) 
(“ ‘[F]ederal  preemption  is  an  affirmative  defense  upon  which  the 
defendants  bear  the  burden  of  proof ’ ”  (quoting  Fifth  Third  Bank  v. 
CSX Corp., 415 F. 3d 741, 745 (CA7 2005))).