Document ID: ./input/supremecourt_opinions/opinions/22pdf/21-1496_d18f.pdf
Page Number: 15

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

9 

Opinion of the Court 

1 

Long  regarded  as  a  leading  case  on  civil  aiding-and- 
abetting  and  conspiracy  liability,  see  130  Stat.  852,  Hal-
berstam  arose  from  a  distinctive  fact  pattern.    Bernard 
Welch  was  a  serial  burglar  who  had  killed  Michael  Hal-
berstam during a break-in.  705 F. 2d, at 474.  Halberstam’s 
estate then sued Welch’s live-in partner, Linda Hamilton, 
for aiding and abetting and conspiring with Welch.  Id., at 
474, 476.7  Hamilton was not present for Halberstam’s mur-
der, or even allegedly aware of the murder.  See id., at 474– 
476.  But the facts made clear that “[s]he was a willing part-
ner  in  [Welch’s]  criminal  activities.”    Id.,  at  474  (internal 
quotation marks omitted).  Hamilton had lived with Welch 
for five years, during which time the couple had risen from
modest  circumstances  to  possess  a  substantial  fortune. 
Ibid.  This rapid ascent was remarkable because Welch had
no  outside  employment.    Id.,  at  475.    Rather,  he  left  the  
house most evenings and returned with antiques, jewelry,
and precious metals—some of which he melted down into
gold and silver ingots by using a smelting furnace that he 
had  installed  in  their  garage.  Meanwhile,  Hamilton  did 
bookkeeping  work  for  Welch’s  “business,”  facilitating  the 
sale of those stolen goods.  Ibid.  She had Welch’s customers 
make  checks  payable  to  her,  falsified  her  tax  returns  at
Welch’s direction, and kept records of incoming payments
from Welch’s customers—with no records of outgoing funds 
to his “suppliers.”  Ibid.  Their arrangement continued until 
Welch was arrested after he killed Halberstam while bur-
glarizing Halberstam’s home.  Ibid. 

To  determine  Hamilton’s  liability,  the  D. C.  Circuit  un-
dertook an extensive survey of the common law, examining 

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7 Halberstam’s estate also sued Welch himself; a default judgment was
entered against Welch, who did not appeal.  See Halberstam, 705 F. 2d, 
at 474.