                 FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,                  No. 05-50191
                Plaintiff-Appellee,
               v.                            D.C. No.
                                          CR-03-00049-DDP
MATTHEW HENRY WEBER,
                                             OPINION
             Defendant-Appellant.
                                      
       Appeal from the United States District Court
          for the Central District of California
       Dean D. Pregerson, District Judge, Presiding

                  Argued and Submitted
         February 13, 2006—Pasadena, California

                    Filed June 20, 2006

    Before: William C. Canby, Jr., John T. Noonan, and
            Marsha S. Berzon, Circuit Judges.

               Opinion by Judge Berzon;
              Concurrence by Judge Noonan




                           6797
                      UNITED STATES v. WEBER                       6801




                             COUNSEL

Maria Stratton, Federal Public Defender, and Jonathan D.
Libby, Deputy Federal Public Defender, Los Angeles, Cali-
fornia, for defendant-appellant Matthew Henry Weber.

Debra Wong Yang, United States Attorney, Thomas P.
O’Brien, Assistant United States Attorney, and Jennifer Cor-
bet, Assistant United States Attorney, Los Angeles, Califor-
nia, for plaintiff-appellee United States of America.


                              OPINION

BERZON, Circuit Judge:

   Penile plethysmograph testing is a procedure that “involves
placing a pressure-sensitive device around a man’s penis, pre-
senting him with an array of sexually stimulating images, and
determining his level of sexual attraction by measuring min-
ute changes in his erectile responses.” Jason R. Odeshoo, Of
Penology and Perversity: The Use of Penile Plethysmography
on Convicted Child Sex Offenders, 14 TEMP. POL. & CIV. RTS.
L. REV. 1, 2 (2004). Although one would expect to find a
description of such a procedure gracing the pages of a George
Orwell novel rather than the Federal Reporter, plethysmo-
graph testing1 has become routine in the treatment of sexual
  1
   In addition to penile plethysmograph testing, there is a corresponding
procedure for women, known as “vaginal plethysmography.” See
6802                   UNITED STATES v. WEBER
offenders and is often imposed as a condition of supervised
release. We address the procedures that must be followed
before a district judge may impose such a requirement on a
criminal defendant.

                                     I.

   In May of 2001, an electronics store technician discovered
several images of child pornography on the hard drive of a
computer that the defendant, Matthew Henry Weber, had
brought in for repairs. The manager of the store informed the
Los Angeles Police Department of the images, which con-
tacted the FBI. When Weber arrived to pick up his computer,
he was interviewed by an FBI agent about the images. Weber
claimed to be unaware of the child pornography images on his
computer. The FBI seized Weber’s computer and conducted
a full forensic examination of the hard drive, uncovering hun-
dreds of images depicting children engaged in sexually
explicit activity.

   On January 17, 2003, a grand jury in the Central District of
California returned a one-count indictment charging Weber
with possession of child pornography in violation of 18
U.S.C. § 2252A(a)(5)(B).2 Weber subsequently pleaded guilty
to the single count in the indictment, pursuant to a plea agree-
ment with the U.S. Attorney’s Office. On March 4, 2005, the
district court sentenced the defendant to twenty-seven months
imprisonment and three years of supervised release.

  In preparing the presentence report (PSR), the Probation
Office proposed that twenty special conditions be imposed as
specific terms of Weber’s supervised release. Among them
was Condition Nine, the requirement that Weber

Odeshoo, supra, at 2 n.9. All references in this opinion to the general term
“plethysmograph testing” cover only penile plethysmograph testing.
  2
    All statutory references in this opinion are to Title 18 of the United
States Code, unless otherwise indicated.
                       UNITED STATES v. WEBER                        6803
      participate in a psychological/psychiatric counseling
      and/or a sex offender treatment program, which may
      include inpatient treatment, as approved and directed
      by the Probation Officer. The defendant shall abide
      by all rules, requirements, and conditions, of such
      program, including submission to risk assessment
      evaluation(s), and physiological testing, such as
      polygraph, plethysmograph, and Abel testing,[3] and
      shall take all prescribed medication.

As justification for the proposed conditions of supervised
release, the PSR stated:

      During the period of supervised release, it is impera-
      tive that the defendant, who has mental health issue
      [sic], continue to receive mental health treatment and
      counseling. Further, it is recommended that the
      defendant continue sex offender treatment, and to be
      subject to intensive supervision to monitor the defen-
      dant’s progress. Meanwhile, these special conditions
      are necessary to protect the public as the defendant
      undergoes treatment. . . . Conditions Nos. 3 to 5, and
      8 to 19 have been recommended as a result of the
      instant offense involving the possession of child por-
      nography, which was collected and stored using his
      computer, and the history and characteristics of the
      defendant.

   In his written objections to the PSR and orally at the sen-
tencing hearing, Weber objected to only one aspect of his
supervised release — the requirement that he submit to
plethysmograph testing.4 The district court declined to strike
that condition, stating:
  3
     Abel testing, another procedure used in sexual offender treatment pro-
grams, “involves presenting individuals with non-erotic pictures of chil-
dren and adults and determining sexual interest by measuring how long a
person spends viewing each picture.” Odeshoo, supra, at 13.
   4
     We address Weber’s additional challenges to his supervised release
conditions, raised for the first time on appeal, in a memorandum disposi-
tion filed concurrently with this opinion.
6804                  UNITED STATES v. WEBER
      Now, in terms of [Condition] number nine, the par-
      ticular testing, what I — if you felt for whatever rea-
      son and could support those reasons that whatever
      test was requested was medically not necessary, you
      could certainly ask — express that to the probation
      officer and ask for a hearing, but I intend to keep the
      condition; but you certainly, as in any condition, pro-
      bation — or for supervised release, you would have
      the ability to request a modification.

The district court overruled Weber’s objection and incorpo-
rated all of the proposed conditions into the judgment and
commitment order. Weber timely appealed.

                                   II.

   Before turning to the merits of Weber’s appeal, we consider
whether Weber’s claim is ripe for review. Although neither
party raises the issue of ripeness, because “[t]he constitutional
component of ripeness is a jurisdictional prerequisite,” United
States v. Antelope, 395 F.3d 1128, 1132 (9th Cir. 2005), we
are obligated to address the matter on our own motion “to
ensure that proper subject matter jurisdiction exists to hear the
case,” Poland v. Stewart, 117 F.3d 1094, 1104 (9th Cir.
1997).

   Condition Nine requires Weber to participate in a sexual
offender treatment program and submit to various tests,
including plethysmograph testing, as a part of that program.
There is nothing in the record indicating that Weber has yet
been ordered to undergo plethysmograph testing and it is not
certain that he will ever be ordered to do so.5 That determina-
tion will presumably be made by Weber’s probation officer in
consultation with the appropriate treatment personnel.
Weber’s refusal to submit to plethysmograph testing once
  5
   At present, Weber has completed his prison sentence and is serving his
term of supervised release.
                    UNITED STATES v. WEBER                   6805
ordered would place him in violation of the terms of his
supervised release.

   [1] A defendant need not refuse to abide by a condition of
supervised release to challenge its legality on direct appeal
from the imposition of sentence. In United States v. Williams,
356 F.3d 1045, 1049-51 (9th Cir. 2004), the defendant
objected to the condition of his supervised release that
required him to take psychotropic and other medications pre-
scribed for treatment of his mental illness. Although there was
no evidence that the defendant had refused to take any such
medications, we rejected the government’s argument that
adjudication of the propriety of the condition was premature.
Id. at 1051. Rather, we held the jurisdictional prerequisite of
ripeness does not require “violation of a specified supervised
release condition to permit appellate review.” Id.

   Relying on Williams, we recently rejected a similar argu-
ment by the government that a challenge to a supervised
release condition that depended on several contingencies was
unripe for appellate review. See United States v. Rodriguez-
Rodriguez, 441 F.3d 767, 771-72 (9th Cir. 2006). In
Rodriguez-Rodriguez, the defendant was convicted of illegal
reentry following deportation and was sentenced to a prison
term of seventy-seven months, to be followed by a three-year
term of supervised release. Id. at 769. Among the conditions
of his supervised release was a requirement that he report to
the probation officer within seventy-two hours of his release
from custody or reentry into the United States. Id. The gov-
ernment claimed Rodriguez-Rodriguez’s challenge to the con-
dition was not ripe because it depended on a number of
contingencies that had yet to occur, in particular, the comple-
tion of his prison term, deportation, and illegal reentry into the
United States. Id. at 771. Unpersuaded, we held that the
defendant could raise a facial challenge to the reporting con-
dition as it was a part of the sentence imposed — a final judg-
ment subject to immediate appeal pursuant to § 3742(a). Id.
at 771-72.
6806                UNITED STATES v. WEBER
   [2] The same is true here. The silence in the record as to
whether Weber has previously had to undergo plethysmo-
graph testing or will have to do so at some point in the future
does not make this case unripe for review. A term of super-
vised release, even if contingent, is part and parcel of the
defendant’s sentence and can be challenged on direct appeal.
Accordingly, there is no jurisdictional barrier to our consider-
ation of the merits.

                              III.

  We begin our merits analysis with a discussion of several
governing principles.

A.     Statutory Framework

   [3] Although the consideration of plethysmograph testing
as a term of supervised release is a question of first impres-
sion in this circuit, we are guided in our analysis by the statu-
tory requirements governing the imposition of conditions of
supervised release and by our prior case law interpreting those
requirements. We have repeatedly held that a district court
enjoys significant discretion in crafting terms of supervised
release for criminal defendants, including the authority to
impose restrictions that infringe on fundamental rights. See
United States v. T.M., 330 F.3d 1235, 1239-40 (9th Cir.
2003); United States v. Bee, 162 F.3d 1232, 1234 (9th Cir.
1998). In fashioning conditions of supervised release, a dis-
trict court “has at its disposal all of the evidence, its own
impressions of a defendant, and wide latitude.” Williams, 356
F.3d at 1052. In light of this “wide latitude,” we give consid-
erable deference to a district court’s determination of the
appropriate supervised release conditions, reviewing those
conditions deferentially, for abuse of discretion. Id.

  [4] A district court’s discretion in this regard is not, how-
ever, boundless. The principal statute governing a district
                      UNITED STATES v. WEBER                       6807
court’s ability to impose conditions of supervised release is
§ 3583. Section 3583(c) states:

      The court, in determining whether to include a term
      of supervised release, and, if a term of supervised
      release is to be included, in determining the length
      of the term and the conditions of supervised release,
      shall consider the factors set forth in section
      3553(a)(1), (a)(2)(B), (a)(2)(C), (a)(2)(D), (a)(4),
      (a)(5), (a)(6), and (a)(7).

The cross-referenced § 3553(a) factors that are of particular
relevance here direct a court to consider:

      (1) the nature and circumstances of the offense and
      the history and characteristics of the defendant;

      (2)   the need for the sentence imposed—

            ...

            (B) to afford adequate deterrence to crim-
            inal conduct;

            (C) to protect the public from further
            crimes of the defendant; and

            (D) to provide the defendant with needed
            educational or vocational training, medical
            care, or other correctional treatment in the
            most effective manner.

   In addition to setting forth certain mandatory conditions of
supervised release, § 3583(d) permits a district court to
impose any condition it deems appropriate,6 so long as the
discretionary condition
  6
    In addition to permitting a district court to design any supervised
release condition it deems appropriate, § 3583(d) specifically enumerates
6808                    UNITED STATES v. WEBER
     (1) is reasonably related to the factors set forth in
     section 3553(a)(1), (a)(2)(B), (a)(2)(C), and
     (a)(2)(D);

     (2) involves no greater deprivation of liberty than
     is reasonably necessary for the purposes set forth in
     section 3553(a)(2)(B), (a)(2)(C), and (a)(2)(D); and

     (3) is consistent with any pertinent policy state-
     ments issued by the Sentencing Commission pursu-
     ant to 28 U.S.C. 994(a).[7]

   [5] Under this statutory scheme, then, conditions of super-
vised release8 “are permissible only if they are reasonably
related to the goal of deterrence, protection of the public, or
rehabilitation of the offender.” T.M., 330 F.3d at 1240. “Con-
ditions of supervised release must relate to these purposes, but
may be unrelated to one or more of [them], so long as they

as permissible conditions a number of discretionary conditions of proba-
tion catalogued at § 3563(b). Relevant here is § 3563(b)(9), which pro-
vides that a district court may require a defendant to “undergo available
medical, psychiatric, or psychological treatment, including treatment for
drug or alcohol dependency, as specified by the court, and remain in a
specified institution if required for that purpose.”
   7
     The United States Sentencing Guidelines Manual contains a policy
statement that recommends the imposition of sex offender treatment pro-
grams for defendants convicted of a sex offense. See U.S.S.G. § 5D1.3(d)
(7)(A). The Guidelines do not, however, specify the particulars of such
treatment programs and do not mention the plethysmograph testing at
issue here.
   8
     As mentioned earlier, § 3583(d) provides for a number of mandatory
conditions of supervised release that are to be imposed by the district court
in certain circumstances. The statutory framework we have catalogued,
however, is applicable to discretionary conditions that a district court may
choose to impose on a defendant. This case deals with such a condition.
Any reference in this opinion to the standards governing “supervised
release conditions” should be understood as referring to only discretionary
supervised release conditions.
                    UNITED STATES v. WEBER                  6809
are sufficiently related to the others.” Bee, 162 F.3d at 1235
(alteration in original) (internal quotation marks omitted). In
addition, a supervised release condition need not relate to the
offense of conviction, as long as it satisfies one of the above
goals. See T.M., 330 F.3d at 1240. Finally, even if a proposed
condition otherwise meets the statutory requirements of
§ 3553(a), it still must “involve ‘no greater deprivation of lib-
erty than is reasonably necessary for the purposes’ of super-
vised release.” Id. (quoting § 3583(d)(2)).

B.   Burden of Justification

   [6] Although our case law has repeatedly explained the
statutory framework governing the imposition of supervised
release terms, we have not had occasion clearly to delineate
which party bears the burden of demonstrating that a discre-
tionary supervised release condition is appropriate in a given
case. We think the answer to this question is fairly evident in
light of the above statutory requirements and our case law dis-
cussing the burden of proof at sentencing generally.

   As we have explained, supervised release conditions “are
permissible only if they are reasonably related” to the goals of
deterrence, public protection, and rehabilitation. T.M., 330
F.3d at 1240 (emphasis added). In addition, the condition
must “involve[ ] no greater deprivation of liberty than is rea-
sonably necessary” to meet those purposes. § 3583(d)(2)
(emphasis added). In light of the statute’s recognition that
supervised release conditions put a defendant’s liberty at
stake, the burden should fall on the government to demon-
strate that the statutory standards have been met.

   [7] The determination that the burden to justify a condition
of supervised release should rest with the government is all
the more apparent when viewed in light of our case law allo-
cating the burden for other aspects of sentencing. We have
held that the government bears “the burden of proving the
facts necessary to establish the base offense level” under the
6810                    UNITED STATES v. WEBER
United States Sentencing Guidelines. United States v. How-
ard, 894 F.2d 1085, 1090 (9th Cir. 1990). That conclusion
was premised on the fact that it is “the government [that] is
initially invoking the court’s power to incarcerate a person.”
Id. Similarly, it is the government that bears the burden of
establishing that the offense level should be raised through
enhancements (although the defendant bears the burden when
he seeks to have the offense level lowered through downward
adjustments). Id. at 1090. In support of our holding in How-
ard, we relied on the Third Circuit’s statement that “[o]ne
who affirmatively seeks special favor at sentencing has the
burden of proving why it should be bestowed.” United States
v. McDowell, 888 F.2d 285, 291 (3d Cir. 1989) (alteration in
original) (quoting United States v. Garcia, 544 F.2d 681, 685-
86 (3d Cir. 1976)).

   [8] We hold that the same rule applies with regard to a
government-supported imposition of a discretionary condition
of supervised release. We have long held that a term of super-
vised release is part of a defendant’s sentence, see United
States v. Soto-Olivas, 44 F.3d 788, 790 (9th Cir. 1995), and,
like imprisonment, restricts a defendant’s liberty and funda-
mental rights, see Williams, 356 F.3d at 1052-53; United
States v. Bolinger, 940 F.2d 478, 480 (9th Cir. 1991). As a
result, when the government seeks to restrict a defendant’s
liberty through a term of supervised release, it shoulders the
burden of proving that a particular condition of supervised
release involves no greater deprivation of liberty than is rea-
sonably necessary to serve the goals of supervised release.9
  9
    Our conclusion as to the proper allocation of the burden of proof at the
imposition of a condition of supervised release is further supported by
case law considering which party bears the burden of proof in other pro-
ceedings concerning supervised release. If a defendant violates a condition
of his supervised release, a district court may revoke his supervised release
and impose a term of imprisonment. See § 3583(e)(3). We have held that,
in such a proceeding, it is the government that bears the burden to demon-
strate that a defendant has violated a condition of his supervised release.
                        UNITED STATES v. WEBER                          6811
C.     Procedural Requirements

   In applying the substantive statutory standards governing
the imposition of supervised release conditions, we have had
occasion to consider the procedural steps a district court must
take before imposing certain conditions on a criminal defen-
dant as a term of his supervised release. In United States v.
Rearden, 349 F.3d 608 (9th Cir. 2003), we held that a district
court is not generally required “to articulate on the record at
sentencing the reasons for imposing each condition.” Id. at
619. Our holding was premised on the circumstances that in
that case, (1) the defendant was on notice of the conditions
that would be imposed, and (2) the PSR had adequately
“spelled out the relationship between them and the factors set
forth in § 3583(d) in detail.” Id.; see also United States v.
Dupas, 419 F.3d 916, 922 (9th Cir. 2005) (noting Rearden’s
general rule that “an explicit statement of reasons is not abso-
lutely required by 18 U.S.C. § 3583(d)”), cert. denied, 126
S. Ct. 1484 (2006).10

     We subsequently fashioned an exception to Rearden’s gen-

See United States v. Turner, 312 F.3d 1137, 1142 (9th Cir. 2002); Soto-
Olivas, 44 F.3d at 792. Likewise, a district court can terminate supervised
release early and discharge the defendant, provided he has served at least
one year of his supervised release term. See § 3583(e)(1). In that situation,
courts have required the defendant, as the party receiving the benefit of
early termination, to demonstrate that such a course of action is justified.
See United States v. Weintraub, 371 F. Supp. 2d 164, 167 (D. Conn.
2005); United States v. McKay, 352 F. Supp. 2d 359, 361 (E.D.N.Y.
2005).
   10
      We note that some of our sister circuits are in disagreement with our
general approach, holding instead that § 3553(c), which requires a district
court to “state in open court the reasons for its imposition of the particular
sentence,” requires an explanation for each supervised release condition.
See United States v. Loy, 191 F.3d 360, 371 (3d Cir. 1999) (remanding to
allow the district court the opportunity to articulate reasons for imposing
specific conditions, so as to ensure effective appellate review); United
States v. Edgin, 92 F.3d 1044, 1049 (10th Cir. 1996) (same).
6812                  UNITED STATES v. WEBER
eral rule that a district court need not articulate specific rea-
sons for imposing a condition of supervised release. In
Williams, we considered a term of supervised release that
required a defendant to “take such psychotropic and other
medications prescribed for him.”11 356 F.3d at 1047 (footnote
omitted). We held in Williams that, in light of the particularly
significant liberty interest at stake, a district court is required,
before ordering such a condition, to “make on-the-record,
medically-grounded findings that court-ordered medication is
necessary to accomplish one or more of the factors listed in
§ 3583(d)(1).” Id. at 1057. We also concluded that a district
court must make an explicit finding that the condition “in-
volves no greater deprivation of liberty than is reasonably
necessary.” Id. (quoting § 3583(d)(2)). Although we recog-
nized in Williams that our previous decision in Rearden does
not ordinarily require a district court to make such specific
findings before imposing a term of supervised release, we
held that when a supervised release condition involves an
especially significant liberty interest, such as a requirement to
take psychotropic medications, Rearden’s general rule does
not apply. Id. at 1055.

   Our conclusion in Williams was guided by the Supreme
Court’s decisions in Washington v. Harper, 494 U.S. 210
(1990), Riggins v. Nevada, 504 U.S. 127 (1992), and Sell v.
United States, 539 U.S. 166 (2003), each of which addressed
the law governing forced medication. See Williams, 356 F.3d
at 1053-56. In light of those decisions, we concluded that “an
order compelling a person to take antipsychotic medication is
an especially grave infringement of liberty.” Id. at 1055. The
due process liberty interest at stake in Williams, we noted, is
grounded in the dual notions that such drugs interfere with an
individual’s personal autonomy and that such drugs have the
potential for serious negative side effects. Id. at 1054. We
concluded that, because of the severity of the infringement, “a
  11
    We read the term “psychotropic” narrowly, so as to “encompass only
‘antipsychotic’ or ‘neuroleptic’ drugs.” Williams, 356 F.3d at 1047 n.2.
                       UNITED STATES v. WEBER                       6813
thorough inquiry is required before a court may issue” an
order making forced psychotropic medication a condition of
supervised release. Id. at 1055.

   We were careful to note in Williams that our holding did
not preclude a district court from ordering, as a term of super-
vised release, that a defendant take certain prescribed medica-
tions. Id. at 1055-56. Rather, our holding was that before
mandating such a condition, a district court must make a spe-
cific “finding of overriding justification and a determination
of medical appropriateness.” Id. at 1056 (internal quotation
marks omitted) (quoting Riggins, 504 U.S. at 135).

   [9] In light of Rearden and Williams, the procedural
requirements governing a district court’s imposition of a con-
dition of supervised release may be summarized as follows:
We will generally not require a district court to articulate the
reasons behind imposing a certain condition. If, however, the
condition implicates a particularly significant liberty interest
of the defendant, then the district court must support its deci-
sion on the record with record evidence that the condition of
supervised release sought to be imposed is “necessary to
accomplish one or more of the factors listed in § 3583(d)(1)”
and “involves no greater deprivation of liberty than is reason-
ably necessary.” Williams, 356 F.3d at 1057 (internal quota-
tion marks omitted) (quoting § 3583(d)(2)).

                                  IV.

   In light of these governing principles, we turn our attention
to the specifics of penile plethysmograph testing. Weber
argues that the requirement that he submit to plethysmograph
testing should be vacated because such testing (1) is not rea-
sonably related to the purposes of deterrence, rehabilitation,
or protection of the public, and (2) even if it does satisfy one
of the above purposes, the testing requirement results in a
greater deprivation of liberty than is reasonably necessary.12
  12
    We have previously approved of a condition of supervised release that
required a defendant to participate in a sexual offender treatment program
6814                    UNITED STATES v. WEBER
To properly assess these claims, we consider both the nature
of the testing at issue and the reception it has received among
courts, psychologists, and academics.13

and “follow all other lifestyle restrictions or treatment requirements
imposed by defendant’s therapist.” United States v. Fellows, 157 F.3d
1197, 1203-04 (9th Cir. 1998). We held that the requirement that the
defendant abide by the treatment conditions imposed by his therapist was
neither overly broad nor an improper delegation of the district court’s
authority, reasoning that “[t]he court cannot be expected to design and
implement the particularities of a treatment program” and that the defen-
dant’s therapist “is in the best position to know what lifestyle restrictions
are necessary to enhance his treatment and reduce the likelihood that he
will re-offend.” Id. at 1204. We also stated that “[u]nless [the defendant]
is required to comply with those restrictions, he will not receive the full
benefit of the treatment program.” Id. Fellows had no reason to, and did
not, consider the propriety of any specific aspect of sexual offender treat-
ment programs, including plethysmograph testing, and does not inform
our inquiry here.
    13
       In the proceedings before the district court, both Weber and the gov-
ernment introduced a number of secondary sources, including psychologi-
cal journals, in support of their respective positions on the propriety of
plethysmograph testing. The discussion that follows relies on some of
those sources, as well as others, to describe the nature of plethysmograph
testing and the corresponding praise and criticism it has received. The
broad propositions for which we rely on these sources for support were all
litigated before the district court, although not all of the psychological
reports were cited by the parties. Relying on such sources is not novel. In
considering the liberty interest of an individual to be free from forced
medication, the Supreme Court relied on various literature from the psy-
chological field. See Harper, 494 U.S. at 234 n.13. We have also previ-
ously relied on secondary sources to inform our judgment in similar
circumstances. See Williams, 356 F.3d 1054-55 (citing secondary sources
for the harm caused by antipsychotic medication); Hernandez v. Ashcroft,
345 F.3d 824, 836-38 (9th Cir. 2003) (reviewing secondary sources in the
field of domestic violence); Lopez-Galarza v. INS, 99 F.3d 954, 962-63
(9th Cir. 1996) (reviewing psychological studies and other sources on the
harm caused by rape). As detailed later, we rely on these sources not to
come to a conclusion as to the propriety of plethysmograph testing in this
case or any other, but to explain why district courts must conduct a thor-
ough inquiry on an evidentiary record before imposing such a requirement
as a term of supervised release.
                    UNITED STATES v. WEBER                      6815
A.   The Nature of Plethysmograph Testing

   As noted at the outset, penile plethysmograph is a test
designed to measure a man’s sexual response to various visual
and auditory stimuli. More precisely, the male “places on his
penis a device that measures its circumference and thus the
level of the subject’s arousal as he is shown sexually explicit
slides or listens to sexually explicit audio ‘scenes.’ ”
Berthiaume v. Caron, 142 F.3d 12, 13 (1st Cir. 1998); see
also Doe ex rel. Rudy-Glanzer v. Glanzer, 232 F.3d 1258,
1262 (9th Cir. 2000) (“A penile plethysmograph is a test that
measures, through electric wires attached to a man’s penis,
the reactions that a man has when presented with certain
visual stimuli . . . .”). The following account spells out how
plethysmograph testing works in practice:

        Prior to beginning the test, the subject is typically
     given instructions about what the procedure entails.
     He is then asked to place the device on his penis and
     is instructed to become fully aroused, either via self-
     stimulation or by the presentation of so-called
     “warm-up stimuli,” in order to derive a baseline
     against which to compare later erectile measure-
     ments. After the individual returns to a state of
     detumescence, he is presented with various erotic
     and non-erotic stimuli. He is instructed to let himself
     become aroused in response to any of the materials
     that he finds sexually exciting. These stimuli come
     in one of three modalities — slides, film/video clips,
     and auditory vignettes — though in some cases dif-
     ferent types of stimuli are presented simultaneously.
     The materials depict individuals of different ages
     and genders — in some cases even possessing differ-
     ent anatomical features — and portray sexual scenar-
     ios involving varying degrees of coercion. The
     stimuli may be presented for periods of varying
     length — from mere seconds to four minutes or lon-
     ger.
6816                 UNITED STATES v. WEBER
        Changes in penile dimension are recorded after
     the presentation of each stimulus . . . .

Odeshoo, supra, at 8-9 (footnotes omitted).

   Initially developed by Czech psychiatrist Kurt Freund as a
means to study sexual deviance, plethysmograph testing was
also at one time used by the Czechoslovakian government to
identify and “cure” homosexuals. DAVID M. FRIEDMAN, A MIND
OF ITS OWN: A CULTURAL HISTORY OF THE PENIS 232 (2001).
Today, plethysmograph testing has become rather routine in
adult sexual offender treatment programs, with one survey
noting that approximately one-quarter of adult sex offender
programs employ the procedure. Odeshoo, supra, at 8.
Another survey has placed the relative incidence of the test
among adult sexual offender programs at fifteen percent, a
somewhat lower, yet still considerable, level. See D. Richard
Laws, Penile Plethysmography: Will We Ever Get It Right?,
in SEXUAL DEVIANCE: ISSUES AND CONTROVERSIES 82, 97 (Tony
Ward et al. eds., 2003).

B.     The Significance of the Liberty Interest

   [10] Courts have previously recognized that plethysmo-
graph testing “can [be] help[ful] in the treatment and monitor-
ing of sex offenders.” Glanzer, 232 F.3d at 1266. At the same
time, the First Circuit has noted, putting it mildly, that
plethysmograph testing is likely to “strike most people as
especially unpleasant and offensive.” Berthiaume, 142 F.3d at
16. Although we agree that “there are plenty of ordinary med-
ical procedures that are disagreeable or upsetting to the
patient,” id., this test is not a run-of-the-mill medical proce-
dure. Plethysmograph testing not only encompasses a physical
intrusion but a mental one, involving not only a measure of
the subject’s genitalia but a probing of his innermost thoughts
as well. See Odeshoo, supra, at 23.
                    UNITED STATES v. WEBER                   6817
   [11] Moreover, plethysmograph testing is exceptionally
intrusive in nature and duration. As one commentator has
noted:

    It is true that cavity searches and strip searches are
    deeply invasive, but [plethysmograph testing] is sub-
    stantially more invasive. Cavity searches do not
    involve the minute monitoring of changes in the size
    and shape of a person’s genitalia. Nor do such
    searches last anywhere near the two or three hours
    required for penile plethysmography exams. Nor do
    cavity or strip searches require a person to become
    sexually aroused, or to engage in sexual self-
    stimulation.

Id. (footnote omitted). We note also that “[t]he degree of pri-
vacy afforded to subjects during the procedure varies consid-
erably.” Id. at 8. Sometimes the test is conducted by placing
the patient in a private room away from the clinician, other
times the two are separated by a curtain or one-way mirror.
Id.

   As these descriptions of plethysmograph testing indicate,
the procedure implicates a particularly significant liberty
interest. In reaching this conclusion, we follow the reasoning
of the First Circuit in Harrington v. Almy, 977 F.2d 37, 44
(1st Cir. 1992). Harrington determined that a government
employee had raised sufficient questions as to his due process
interest in refusing his employer’s demand that he submit to
plethysmograph testing to warrant a jury trial on the question
whether the requirement violated substantive due process. Id.

   Harrington considered the strength of the plaintiff’s liberty
interest claim in refusing to submit to plethysmograph testing
in light of Rochin v. California, 342 U.S. 165 (1952), and
Winston v. Lee, 470 U.S. 753 (1985), cases in which the
Supreme Court considered the constitutional interest inherent
in avoiding “unwanted bodily intrusions or manipulations.”
6818                    UNITED STATES v. WEBER
Harrington, 977 F.2d at 43-44. As the First Circuit observed
in Harrington, the governing case law indicates that “nonrou-
tine manipulative intrusions on bodily integrity will be subject
to heightened scrutiny to determine, inter alia, whether there
are less intrusive alternatives available.” Id. at 44. Applying
that standard, the First Circuit concluded:

       A reasonable finder of fact could conclude that
       requiring the plethysmograph involves a substantive
       due process violation. The procedure, from all that
       appears, is hardly routine. One does not have to cul-
       tivate particularly delicate sensibilities to believe
       degrading the process of having a strain gauge
       strapped to an individual’s genitals while sexually
       explicit pictures are displayed in an effort to deter-
       mine his sexual arousal patterns. The procedure
       involves bodily manipulation of the most intimate
       sort. There has been no showing regarding the proce-
       dure’s reliability and, in light of other psychological
       evaluative tools available, there has been no demon-
       stration that other less intrusive means of obtaining
       the relevant information are not sufficient.

Id.

   [12] Although, given the supervised release context, we are
not considering the same substantive due process question at
issue in Harrington, Harrington rests on the premise that the
strong liberty interest in one’s own bodily integrity is
impaired by the plethysmograph procedure.14 We find the
First Circuit’s analysis persuasive in this regard.
  14
     As stated above, Weber has objected to the requirement that he submit
to plethysmograph testing on statutory grounds — that such testing is not
reasonably related to the goals of supervised release and would result in
a greater deprivation of liberty than necessary. See § 3583(d). He has not
claimed that plethysmograph testing as a condition of supervised release
is a violation of his substantive due process rights. Because the issue is not
before us, we express no opinion on the question whether requiring
plethysmograph testing as a condition of supervised release amounts to a
substantive due process violation.
                     UNITED STATES v. WEBER                    6819
   Similarly, Coleman v. Dretke, 395 F.3d 216, 223 & n.28
(5th Cir. 2004), cert. denied 126 S. Ct. 427 (2005), supports
the conclusion that plethysmograph testing implicates a par-
ticularly significant liberty interest. In that case, the Fifth Cir-
cuit considered a sex offender treatment program which
included plethysmograph testing and was imposed by Texas
on criminal defendants released on mandatory supervision or
parole. Id. Referring specifically to plethysmograph testing
and citing Harrington, Coleman held that “due to its highly
invasive nature, Texas’s sex offender therapy program is
‘qualitatively different’ from other conditions which may
attend an inmate’s release” and that the Due Process Clause
“provides [an individual] with a liberty interest in freedom
from the stigma and compelled treatment on which his parole
was conditioned” sufficient to require especially stringent
procedural protections. Id. at 223.

C.   Reactions to Plethysmograph Testing

   [13] Our concerns with plethysmograph testing do not rest
solely on the invasive nature of the test itself. In addition, the
accuracy and reliability of penile plethysmograph testing have
been severely questioned. The American Psychiatric Associa-
tion has expressed reservations about the procedure, observ-
ing: “The reliability and validity of this procedure in clinical
assessment have not been well established, and clinical expe-
rience suggests that subjects can stimulate response by manip-
ulating mental images.” AM. PSYCHIATRIC ASS’N, DIAGNOSTIC
AND STATISTICAL MANUAL OF MENTAL DISORDERS: DSM-IV-TR
567 (4th ed. 2000); see also W.L. Marshall & Yolanda M.
Fernandez, Phallometric Testing with Sexual Offenders: Lim-
its to Its Value, 20 CLINICAL PSYCHOL. REV. 807, 810-813
(2000) (questioning the reliability of phallometric testing,
such as plethysmograph testing); Odeshoo, supra, at 10-13
(detailing a number of problems with plethysmograph testing,
among them inconsistent results as to the test’s reliability and
validity).
6820                UNITED STATES v. WEBER
   A predominant concern with plethysmograph testing is its
susceptibility to manipulation via faking. Several studies have
acknowledged that subjects can control their sexual arousal
during the test, thereby posing a threat to the validity of
plethysmograph testing. See, e.g., James G. Barker & Robert
J. Howell, The Plethysmograph: A Review of Recent Litera-
ture, 20 BULL. AM. ACAD. PSYCHIATRY & L. 13, 21-23 (1992).
According to one source, “[s]everal studies have shown that
normal subjects can significantly inhibit their arousal by using
mental activities to distract themselves, despite a clear indica-
tion that they were attending to the stimuli.” Marshall & Fer-
nandez, supra, at 810. Because “it appears virtually
impossible to prevent or detect dissimulation . . . faking will
always constitute some undetermined degree of threat to the
validity of phallometric assessments.” Id. at 811; see also
Walter T. Simon & Peter G.W. Schouten, The Plethysmo-
graph Reconsidered: Comments on Barker and Howell, 21
BULL. AM. ACAD. PSYCHIATRY & L. 505, 510 (1993) (“The vul-
nerability of the plethysmograph to voluntary control has been
widely documented and is a major concern in the use of the
test with offenders.”).

   [14] Plethysmograph testing has also been sharply criti-
cized as lacking “uniform administration and scoring guide-
lines.” See Simon & Schouten, supra, at 510; see also
Odeshoo, supra, at 12-13 (noting a lack of standardization in
administration of plethysmograph testing). One researcher
noted well over a dozen potential sources of variation among
different assessments, including the type of measuring device
and stimuli that are used, the characteristics of the test, and
the setting in which it is conducted. See Laws, supra, at 87-
88. The lack of standard procedures governing plethysmo-
graph testing has led one pair of commentators to conclude
that “research data as well as individual findings derived by
plethysmograph must be considered idiosyncratic [and] una-
menable to normative comparisons, if not impossible to inter-
pret from a traditional psychometric perspective.” Simon &
Schouten, supra, at 511. The lack of uniform standards is
                        UNITED STATES v. WEBER                         6821
compounded by reports that indicate a lack of formal training
for clinicians administering the test. See Laws, supra, at 87
(characterizing as “truly appalling” one survey’s findings that
seventy-six percent of plethysmograph technicians received
one week or less of training and eighteen percent received no
training whatsoever).

   The supporters of plethysmograph testing acknowledge its
limitations. See Barker & Howell, supra, at 13, 22-23 (noting
that while some research supports the notion that plethysmo-
graph testing “is a reliable and valid method of objectively
measuring and assessing the erectile response in male sexual
offenders,” the propensity for faking and lack of standards
poses a challenge to accurate use of such testing). In addition,
at least one former advocate of the procedure has since
changed his tune. See Laws, supra, at 82-84, 99 (explaining
the author’s account of why his former faith in plethysmo-
graph testing has subsequently been “seriously eroded”).15
  15
     Courts have uniformly declared that the results of such tests are “inad-
missible as evidence because there are no accepted standards for this test
in the scientific community.” Glanzer, 232 F.3d at 1266; see also United
States v. Powers, 59 F.3d 1460, 1470-71 (4th Cir. 1995) (concluding that
a district court did not abuse its discretion in denying the admissibility of
expert testimony on plethysmograph testing under Daubert v. Merrell
Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), because, although “use-
ful for treatment of sex offenders” there was “extensive, unanswered evi-
dence weighing against the scientific validity of the penile
plethysmograph test”); Laws, supra, at 95-97 (noting the unlikelihood that
plethysmograph testing can satisfy several of the Daubert criteria). But see
Alex Kozinski, Brave New World, 30 U.C. DAVIS L. REV. 997, 1008-09
(1997) (suggesting that in certain circumstances plethysmograph testing
might meet the requisites of Daubert). Furthermore, although the First Cir-
cuit noted that “the plethysmograph is widely used in the scientific com-
munity for the treatment of pedophilia,” that court also stated that “its use
for screening is debatable and the scientific community is not of one
mind.” Berthiaume, 142 F.3d at 17; see also Simon & Schouten, supra,
at 511 (plethysmography’s “scientific status remains that of an experimen-
tal technique”).
6822                UNITED STATES v. WEBER
   Despite these criticisms, plethysmograph testing has been
recognized by some psychologists and researchers as a useful
technique in the treatment of sexual offenders. “The ideal
application for the plethysmograph is the assessment and
treatment of known sex offenders.” Barker & Howell, supra,
at 18. Its role in a treatment program is to aid in identifying
whether an individual exhibits a sexual response to deviant
stimuli and determining whether a prescribed course of
behavior modification therapy is effective in promoting “non-
deviant arousal.” Id. In particular:

      The plethysmograph can help in identifying offend-
      ers who manifest high levels of arousal to stimuli
      depicting inappropriate sexual activity, or those
      showing very low levels of arousal to stimuli that
      would be considered portraying appropriate sexual
      activity. The plethysmograph can help determine and
      enhance specialized behavior therapy for these
      offenders and evaluate therapeutic efficacy without
      the normal distortion evident in the subject’s self-
      report.

Id.

   Another researcher has differentiated between the appropri-
ate and inappropriate uses of plethysmograph testing: Among
the accepted uses of the procedure, according to that account,
are the “[u]se of erection responses to indicate the need to tar-
get deviant sexual arousal for treatment and to monitor the
effectiveness of that treatment” and the “[u]se of erection
responses to confront subjects who deny having deviant
arousal.” Laws, supra, at 98. That same analysis, however,
cautioned that plethysmograph testing should not be used to
“determine or make statements about whether someone has
committed a specific sexual offense or whether someone ‘fits
the profile’ of a sexual offender.” Id. at 98. Also inappropriate
would be using plethysmograph testing “as a sole criterion to
decide someone’s release from custody or from a treatment
                    UNITED STATES v. WEBER                 6823
program” or “to screen general populations in search of
potential sex offenders.” Id.

D.   Plethysmograph Testing as a Condition of Supervised
     Release

   [15] In light of these observations by courts and commenta-
tors alike, we cannot say categorically that, despite the ques-
tions of reliability, plethysmograph testing can never
reasonably promote at least one, if not all three, of the rele-
vant goals laid out in § 3553(a)(2) — namely, deterrence,
public protection, and rehabilitation. As the Fourth Circuit,
the only circuit to address the permissibility of plethysmo-
graph testing as a condition of supervised release, has held,
plethysmograph testing is regarded as “useful for treatment of
sex offenders” in appropriate circumstances and thus can be
“reasonably related” to “treatment, fostering deterrence, and
protecting the public.” United States v. Dotson, 324 F.3d 256,
261 (4th Cir. 2003) (internal quotation marks omitted) (quot-
ing United States v. Powers, 59 F.3d 1460, 1471 (4th Cir.
1995)); see also Walrath v. United States, 830 F. Supp. 444,
446-47 (N.D. Ill. 1993) (upholding plethysmograph testing as
a condition of parole against Fourth and Fifth Amendment
challenges, concluding that “[t]he fact that two recommended
institutions require the plethysmograph as an evaluative tool
suggests that it serves a useful function in the treatment of
sexual deviance”); State v. Riles, 957 P.2d 655, 668 (Wash.
1998) (upholding plethysmograph testing as part of a treat-
ment program for a sexual offender in light of the observation
that such testing is “an effective method for diagnosing and
treating sex offenders”).

   [16] To so conclude, however, is not the end of the story.
First, although we recognize that plethysmograph testing can
reasonably promote the goals of supervised release, the ques-
tion of whether it will promote those goals in a particular case
must be an individualized determination. Section 3583(d)(1)
requires that conditions of supervised release be “reasonably
6824                   UNITED STATES v. WEBER
related” to “the nature and circumstances of the offense and
the history and characteristics of the defendant.” See
§§ 3583(d)(1), 3553(a)(1). This tailoring requirement is all the
more important in cases such as this, where a particularly
strong liberty interest is at stake. To satisfy the standard that
a supervised release condition be “reasonably related” to the
statutory goals in the particular circumstances, a district court
must consider whether, given the level of intrusion required
by the test, its noted flaws, and its downsides,16 plethysmo-
graph testing is sufficiently likely, given a defendant’s spe-
cific characteristics, to yield sufficiently useful results. Only
a finding that plethysmograph testing is likely given the
defendant’s characteristics and criminal background to reap
its intended benefits can justify the intrusion into a defen-
dant’s significant liberty interest in his own bodily integrity.

   Second, conditions of supervised release must also “involve
‘no greater deprivation of liberty than is reasonably necessary
for the purposes’ of supervised release.” T.M., 330 F.3d at
1240 (quoting § 3583(d)(2)). There are alternatives available
in the treatment of sexual offenders that are considerably less
intrusive than plethysmograph testing and may be sufficiently
accurate. See Laws, supra, at 99; Marshall & Fernandez,
supra, at 817; Odeshoo, supra, at 13-16.
  16
     One of these detriments derives from the fact that plethysmograph
testing involves presenting subjects with various erotic images which,
according to some accounts, can include child pornography. See Odeshoo,
supra, at 33. “Treating” a sexual offender, like Weber, who was convicted
of possession of child pornography by presenting him with images of the
very sort that lead to his conviction is a little like handing a pyromaniac
a lighted match but cautioning him not to use it. The consideration that the
test involves exposing the sexual offender to the very stimuli that other
conditions of supervised release may discourage him from possessing is
one more reason why a careful, on-the-record assessment of the individu-
al’s circumstances, most usefully informed by expert opinion, is necessary
to sort out whether the likely impact of plethysmograph testing, is, on bal-
ance, reasonably related to the statutory purposes of supervised release.
                    UNITED STATES v. WEBER                  6825
   For example, sexual offenders are often treated through
self-reporting interviews, during which the subject is asked
about his sexual preferences. Odeshoo, supra, at 14. Other
sexual offender programs rely on a card-sorting test, which
involves asking the individual to sort cards depicting sexual
images into deviant and non-deviant categories. Id. Although
these techniques have been criticized for their susceptibility to
faking on the part of the subject, see id., plethysmograph test-
ing, as we have observed, is not immune from this criticism.
The effectiveness of these procedures in the treatment of sex-
ual offenders is disputed among the experts, with one com-
mentator noting that “some researchers believe that basic self-
reporting . . . is as effective as [plethysmograph testing] or
other techniques,” id., and another study concluding that “the
psychometric data on these alternative approaches is far less
satisfactory than for phallometrics,” Marshall & Fernandez,
supra, at 817.

   Another non-physiological test which also appears to enjoy
routine use in sexual offender programs is Abel testing. Abel
testing, which was also required in this case but is not chal-
lenged by Weber, involves exhibiting photographs to an indi-
vidual and measuring the length of time he looks at each
picture. See Odeshoo, supra, at 13. This procedure is much
less intrusive into the body and somewhat less intrusive into
the mind of a defendant than plethysmograph testing. Much
like plethysmography, the effectiveness and reliability of Abel
testing is the subject of some debate. See id. at 14; Marshall
& Fernandez, supra, at 817. One researcher, however, has
deemed Abel testing to be a “promising development.” Laws,
supra, at 99. Given that Abel testing is not properly before us,
we do not set forth any opinion as to its propriety in this, or
any other case. We discuss the procedure only to point out the
existence of a less intrusive alternative to plethysmograph
testing that enjoys similar, if not more, support among
researchers. The appropriateness of Abel testing in a particu-
lar case should, of course, be left to the district court judge
and probation officer, with appropriate expert consultation.
6826                   UNITED STATES v. WEBER
   Ordinary polygraph testing is another possible viable alter-
native to plethysmograph testing that can be considered by
district courts as they fashion supervised release conditions.
Already more common in sexual offender treatment programs
than plethysmograph testing, polygraph testing is much less
costly to administer and “appears to be at least as valid and
reliable as the plethysmograph (if not more so).” Odeshoo,
supra, at 14-15. Most importantly, a polygraph examination
“may well be preferable by virtue of its less intrusive and con-
troversial character.” id. at 16.17

   [17] The existence of non-physiological, less-intrusive
alternatives to plethysmograph testing, including interviews,
card-sorting, and Abel and polygraph testing, is, self-
evidently, highly relevant to the question of whether plethys-
mograph testing “involves no greater deprivation of liberty
than is reasonably necessary” to serve the purposes of super-
vised release. § 3583(d)(2); see also T.M., 330 F.3d at 1240.
As we have indicated, imposing such testing as a condition of
supervised release implicates a liberty interest sufficiently
  17
    We recently considered a challenge to a supervised release condition
mandating polygraph testing for a sexual offender as part of his treatment
program. See Antelope, 395 F.3d at 1133-41. The defendant in that case
challenged the polygraph requirement on the grounds that it violated his
Fifth Amendment right against compelled self-incrimination. Id. at 1133.
While we acknowledged the rehabilitative purpose behind the polygraph
questioning, we held that requiring, as a condition of supervised release,
that a defendant answer questions about potential criminal activity in a
polygraph examination was significantly incriminating and coercive to
violate the Fifth Amendment. Id. at 1134-39. That conclusion, however,
did not doom the condition. Rather, we held that a defendant retains his
right against self-incrimination during the required polygraph testing and
can refuse to answer any incriminating questions unless he is granted use-
and-derivative-use immunity under Kastigar v. United States, 406 U.S.
441 (1972). See Antelope, 395 F.3d at 1141 & n.5. After Antelope, then,
a district court may require, as a term of supervised release, that a defen-
dant submit to polygraph testing, provided such a condition comports with
the requirements of § 3583(d), but a defendant retains his Fifth Amend-
ment rights during any such testing.
                       UNITED STATES v. WEBER                         6827
weighty to trigger the enhanced procedural requirements
established in Williams. When viable and effective alterna-
tives exist to plethysmograph testing, a procedure that
involves intrusion on an especially significant liberty interest,
a district court should be hesitant to impose that procedure as
a supervised release condition and may do so only after
explaining on the record why the alternatives are inadequate.

E.   Conclusion

   [18] We conclude that, just as the particularly significant
liberty interest at stake in Williams meant that “a thorough
inquiry is required” before a district court may impose forced
medication as a condition of supervised release, including
“on-the-record medically-grounded findings,” Williams, 356
F.3d at 1055-57, so the particularly significant liberty interest
in being free from plethysmograph testing requires a thor-
ough, on-the-record inquiry into whether the degree of intru-
sion caused by such testing is reasonably necessary “to
accomplish one or more of the factors listed in § 3583(d)(1)”
and “involves no greater deprivation of liberty than is reason-
ably necessary,” given the available alternatives. Id. at 1057.

   One critical determination that must guide a district court’s
inquiry as to whether the government has met its burden to
show that plethysmograph testing is a necessary condition of
a defendant’s supervised release is whether such testing is
reasonably necessary in that particular case to promote the
goals “of deterrence, protection of the public, or rehabilitation
of the offender.” T.M., 330 F.3d at 1240. Making such a
determination requires consideration of evidence that plethys-
mograph testing is reasonably necessary for the particular
defendant based upon his specific psychological profile.18 We
   18
      We note that, in this case, following the investigation into Weber’s
possession of child pornography and the initial seizure of Weber’s com-
puter, it was later discovered that he continued to possess child pornogra-
phy on a second computer. Although this fact alone would be insufficient
to warrant plethysmograph testing, Weber’s apparent inability to control
his desire for child pornography, even after detection by authorities, might
be relevant to a determination of the appropriateness of such testing.
6828                    UNITED STATES v. WEBER
expect that the probation officer or the district court will ordi-
narily consult the views of a psychologist or other expert as
to the propriety of plethysmograph testing for the particular
defendant, although there may be circumstances in which it is
not necessary to do so. Cf. Williams, 356 F.3d at 1056 (requir-
ing findings bases on a “medically-informed record” before
antipsychotic medication could be required as a term of super-
vised release).

   Additionally, when engaging in this inquiry the district
court must consider the particular sexual offenses committed
by the defendant, as well as related offenses likely to be com-
mitted if he is not treated. Weber objects to the imposition of
plethysmograph testing on the ground that his crime, posses-
sion of child pornography, does not warrant such a procedure,
contending that plethysmograph testing is appropriate only for
individuals who have committed, or attempted to commit,
sexual acts directly against children. The district court is not,
however, restricted to the crime of conviction in applying the
“reasonably related” standard.19 Still, a generalized assess-
ment based on the class of sex offenders generally, rather than
on the particular sex offenses a defendant has committed or
related offenses he is likely to commit if not treated, cannot
fulfill the mandate that a term of supervised release satisfy the
“reasonably related” standard.20
  19
      A supervised release term need not be related to the offense of convic-
tion and instead can “look forward in time to crimes that may be commit-
ted in the future.” See United States v. Wise, 391 F.3d 1027, 1031 (9th Cir.
2004).
   20
      We note that Weber’s claim that plethysmograph testing may have
limited applicability to individuals like him — those who have not com-
mitted an act of sexual abuse — has some support from researchers in the
field. Although studies claim that plethysmograph testing is appropriate
for treatment of “sex offenders,” see Barker & Howell, supra, at 18, one
study of plethysmograph testing has specifically limited the definition of
sexual offenders to “mature males who either coerce an adult female to
have sex with them, or have sex with a child,” Marshall & Fernandez,
supra, at 809. Although recognizing that there are individuals who commit
other sexually offensive acts such as exhibitionism or voyeurism (of which
viewing child pornography is a variety), the authors of that study stated
that “phallometry has either had limited or no application to these popula-
tions.” Id.
                         UNITED STATES v. WEBER                        6829
   In response to Weber’s objection to the plethysmograph
testing requirement, the district court noted that if, in the
future, Weber thought that such testing “was medically not
necessary,” he could “ask for a hearing” or “request a modifi-
cation.” As we have explained, however, the burden is on the
government, not the defendant, to establish at the time of sen-
tencing that plethysmograph testing is both reasonably neces-
sary “to accomplish one or more of the factors listed in
§ 3583(d)(1)” and “involves no greater deprivation of liberty
than is reasonably necessary.”21 Williams, 356 F.3d at 1057
(internal quotation marks omitted). On remand, if the govern-
ment continues to seek submission to plethysmograph testing
as a condition of supervised release, then it must meet its bur-
den of justifying the requirement, and the district court must
make on-the-record findings that it has done so.

   We note that our holding does not displace Rearden’s gen-
eral rule that, so long as the PSR adequately explains the rela-
tionship between proposed conditions of supervised release
and the purposes those conditions are designed to serve, a dis-
trict court usually need not specifically articulate those rea-
sons on the record.22 As we noted in Williams, however, that
  21
      Should circumstances arise after sentencing, while a defendant is serv-
ing his term of supervised release, that would impact the decision of
whether plethysmograph testing is proper, it is possible that on an appro-
priate showing the district court could modify the defendant’s conditions
of supervised release. See § 3583(e)(2); United States v. Miller, 205 F.3d
1098, 1100-01 (9th Cir. 2000).
   22
      We note that even if Rearden were the governing precedent, its requi-
sites almost surely were not met. The PSR did put Weber on notice of the
proposed plethysmograph testing. It did not, however, spell out “in detail”
the relationship between that condition and the statutory requirements for
conditions of supervised release. See Rearden, 349 F.3d at 619. In support
of its recommended conditions of supervised release, the PSR in this case
contained only a general bare bones statement:
       Meanwhile, these special conditions are necessary to protect the
       public as the defendant undergoes treatment[.] Pursuant to 18
       USC 3583(d), conditions of supervised release must be reason-
6830                 UNITED STATES v. WEBER
general rule is subject to limited exceptions. Today, we recog-
nize that the imposition of plethysmograph testing implicates
a sufficiently significant liberty interest to require heightened
procedural protections similar to those established in Wil-
liams. Again, as in Williams with regard to forced medication,
we are not holding that a district court may never impose
plethysmograph testing as a condition of supervised release,
only that “a thorough inquiry is required” before a court may
do so. 356 F.3d at 1055.

                                  V.

   [19] The requirement that Weber submit to plethysmograph
testing as part of his sex offender treatment program was
imposed without the necessary evidentiary record, justifica-
tion, and findings we now hold are required. Accordingly, we
vacate the condition and remand for further proceedings con-
sistent with this opinion.

  VACATED and REMANDED.



NOONAN, Circuit Judge, concurring:

   Judge Berzon’s excellent opinion is deserving of support.
I would, however, go beyond it to hold the Orwellian proce-
dure at issue to be always a violation of the personal dignity
of which prisoners are not deprived. The procedure violates
a prisoner’s bodily integrity by affecting his genitals. The pro-
cedure violates a prisoner’s mental integrity by intruding

   ably related to the nature and circumstances of the offense and
   the history and characteristics of the defendant. Conditions Nos.
   3 to 5, and 8 to 19 have been recommended as a result of the
   instant offense involving the possession of child pornography,
   which was collected and stored using his computer, and the his-
   tory and characteristics of the defendant.
                    UNITED STATES v. WEBER                 6831
images into his brain. The procedure violates a prisoner’s
moral integrity by requiring him to masturbate.

   By committing a crime and being convicted of it, a person
does not cease to be a person. A prisoner is not a mere tool
of the state to be manipulated by it to achieve the purposes the
law has determined appropriate in punishment. The prisoner
retains his humanity and therefore has purposes transcending
those of the state. A prisoner, for example, cannot be forced
into prostitution to aid the state in securing evidence. A pris-
oner, for example, cannot be made to perjure himself in order
to assist a prosecution. Similarly, a prisoner should not be
compelled to stimulate himself sexually in order for the gov-
ernment to get a sense of his current proclivities. There is a
line at which the government must stop. Penile plethysmogra-
phy testing crosses it.
