Document ID: ./input/supremecourt_opinions/opinions/21pdf/20-1410_1an2.pdf
Page Number: 5.0

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

1 

Opinion of the Court 

NOTICE:  This opinion is subject to formal revision before publication in the 
preliminary  print  of  the  United  States  Reports.  Readers  are  requested  to 
notify the Reporter of Decisions, Supreme Court of the United States, Wash-
ington, D. C. 20543, of any typographical or other formal errors, in order that 
corrections may be made before the preliminary print goes to press. 

SUPREME COURT OF THE UNITED STATES 

_________________ 

Nos. 20–1410 and 21–5261 
_________________ 

20–1410 

XIULU RUAN, PETITIONER 
v. 
UNITED STATES 

ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 
APPEALS FOR THE ELEVENTH CIRCUIT 

21–5261 

SHAKEEL KAHN, PETITIONER 
v. 
UNITED STATES 

ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 
APPEALS FOR THE TENTH CIRCUIT 

[June 27, 2022] 

JUSTICE BREYER delivered the opinion of the Court. 
A provision of the Controlled Substances Act, codified at
21 U. S. C. §841, makes it a federal crime, “[e]xcept as au-
thorized[,] . . . for any person knowingly or intentionally . . . 
to manufacture, distribute, or dispense . . . a controlled sub-
stance,” such as opioids.  84 Stat. 1260, 21 U. S. C. §841(a) 
(emphasis added).  Registered doctors may prescribe these
substances  to  their  patients.  But,  as  provided  by  regula-
tion, a prescription is only authorized when a doctor issues
it “for a legitimate medical purpose . . . acting in the usual
course  of  his  professional  practice.”  21  CFR  §1306.04(a)
(2021).