FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

DARIN D. GREENE,                         No. 06-16957
              Plaintiff-Appellant,
              v.                           D.C. No.
                                         CV-04-0917 MCE
SOLANO COUNTY JAIL,
                                            OPINION
             Defendant-Appellee.
                                     
      Appeal from the United States District Court
          for the Eastern District of California
    Morrison C. England, Jr., District Judge, Presiding

                 Argued and Submitted
       October 16, 2007—San Francisco, California

                  Filed January 22, 2008

    Before: Arthur L. Alarcón, David R. Thompson, and
            Richard C. Tallman, Circuit Judges.

               Opinion by Judge Thompson




                           857
                GREENE v. SOLANO COUNTY JAIL              859


                         COUNSEL

Fred Martin, Oakland, California, for the plaintiff-appellant.

Martha M. Stringer, Sacramento, California, for the
defendant-appellee, Rourk.


                         OPINION

THOMPSON, Senior Circuit Judge:

   Darin D. Greene (“Greene”), a former maximum security
prisoner at the Claybank facility of the Solano County jail
860               GREENE v. SOLANO COUNTY JAIL
(“the Claybank jail”), appeals the district court’s summary
judgment as to all claims in favor of the defendant, Solano
County Sheriff’s Lieutenant Peggy Rourk (“Rourk”).

   In his civil rights action against Rourk, Greene alleged that
the Claybank jail’s policy of prohibiting maximum security
prisoners from participating in group worship was a violation
of his rights under the Religious Land Use and Institutional-
ized Persons Act of 2000 (“RLUIPA”), 42 U.S.C. §§ 2000cc
et seq., under the First, Eighth and Fourteenth Amendments,
and under California Penal Code section 4027 (“Penal Code
section 4027”).1 Rourk moved for summary judgment on por-
tions of Greene’s RLUIPA claim. The district court granted
summary judgment in favor of Rourk on the entire RLUIPA
claim and, sua sponte, granted summary judgment in favor of
Rourk on Greene’s 42 U.S.C. § 1983 (“section 1983”) claims
for alleged violations of the First, Eighth and Fourteenth
Amendments, as well as for his claim under Penal Code sec-
tion 4027, and dismissed the case. Greene appeals.

   We have jurisdiction pursuant to 28 U.S.C. §§ 1291 and
1294. Because disputed issues of material fact exist with
regard to Greene’s RLUIPA claim, we reverse the district
court’s summary judgment in favor of Rourk on that claim
and remand it to the district court for further proceedings.
Because Rourk did not meet her burden on summary judg-
ment as to Greene’s section 1983 claims, or as to his Penal
Code section 4027 claim, and because Greene was not given
notice and an opportunity to oppose summary judgment as to
those claims, we vacate the district court’s summary judgment
in favor of Rourk on those claims, and remand them to the
district court as well.
  1
   Greene’s Penal Code section 4027 claim appears to have been raised
for the first time in his opposition to Rourk’s motion for summary judg-
ment. The district court treated the claim as properly pleaded and dis-
missed it in the court’s summary judgment in favor of Rourk.
                GREENE v. SOLANO COUNTY JAIL               861
                    I.   BACKGROUND

   While Greene was awaiting trial on charges of terrorist
threats and false imprisonment, he was housed in the maxi-
mum security area at the Claybank jail for approximately
three months, from June 30, 2003 to October 9, 2003. Greene
alleged, and Rourk confirmed, that numerous times while at
the Claybank jail, Greene requested, and was denied, the
opportunity to attend group religious worship services.
Greene attempted to conduct Bible studies and morning
prayer with a number of other inmates by “yelling through the
corner edge of the cell door” but was ordered to stop because
it was bothering other prisoners, including those who “were
not able to hear the television without being disturbed.” On
September 12, 2003, Greene submitted a grievance, signed by
42 other inmates, requesting that group religious services be
provided for maximum security inmates. Rourk denied the
request, but offered to send a chaplain to visit Greene.

   Greene filed a second grievance requesting that a classroom
at the Claybank jail be provided at least once per week to
inmates in maximum security for group religious services.
This request was denied, but once again a religious visit was
offered. Greene never accepted that offer. He requested, and
was given, a Bible and a copy of “The Daily Bread,” a reli-
gious periodical.

   Greene, then acting pro se and in forma pauperis, filed a
civil rights action in the United States District Court for the
Northern District of California. The case was transferred to
the United States District Court for the Eastern District of
California, and Greene amended his complaint, naming Rourk
as the sole defendant. In his amended complaint, Greene
alleged that Rourk’s refusal to allow group religious worship
by maximum security prisoners at the Claybank jail was a
violation of his rights.
862                GREENE v. SOLANO COUNTY JAIL
   Rourk moved for summary judgment. Her “Notice of
Motion and Motion for Summary Judgment” stated that she
was “entitled to judgment as a matter of law with respect to
the claim for relief under [42 U.S.C.] § 1983 . . . .” In her
Memorandum of Points and Authorities, however, Rourk
focused on Greene’s RLUIPA claim and omitted any discus-
sion as to Greene’s other claims. Greene filed his pro se
response, which was dedicated almost entirely to Rourk’s
RLUIPA arguments.2

   The magistrate judge recommended summary judgment be
granted in favor of Rourk on Greene’s RLUIPA claim. He
also recommended that summary judgment be granted in
favor of Rourk on Greene’s section 1983 claims as well as his
claim under Penal Code section 4027, even though neither
party had briefed those claims. In addition, he recommended
that the action be dismissed. On September 18, 2006, the dis-
trict court followed the magistrate judge’s recommendation
and granted summary judgment in favor of Rourk and dis-
missed the action. This appeal followed.

                         II.   DISCUSSION

  A.    The RLUIPA Claim

   [1] RLUIPA provides in relevant part, that “[n]o govern-
ment shall impose a substantial burden on the religious exer-
cise of a person residing in or confined to an institution . . .
even if the burden results from a rule of general applicabili-
ty,” unless the government establishes that the burden furthers
“a compelling governmental interest,” and does so by “the
least restrictive means.” 42 U.S.C. § 2000cc-1(a)(1)-(2).
RLUIPA defines “religious exercise” to include “any exercise
  2
   Greene made general references to the other claims, i.e., he cited the
standards for various First Amendment violations, but he did not address
his other claims directly, nor did he attempt to argue against summary
judgment as to those claims.
                    GREENE v. SOLANO COUNTY JAIL                        863
of religion, whether or not compelled by, or central to, a sys-
tem of religious belief.” 42 U.S.C. § 2000cc-5(7)(A); Warsol-
dier v. Woodford, 

, 994 (9th Cir. 2005).

    The Supreme Court has recognized RLUIPA as “the latest
of long-running congressional efforts to accord religious exer-
cise heightened protection from government-imposed burdens
. . . .” Cutter v. Wilkinson, 

, 714 (2005). The stat-
ute itself reflects this intent stating, “This chapter shall be
construed in favor of a broad protection of religious exercise,
to the maximum extent permitted by the terms of this chapter
and the Constitution.” 42 U.S.C. § 2000cc-3(g). See also War-

.

   [2] Congress effectuated this intent by distinguishing
RLUIPA from traditional First Amendment jurisprudence in
at least two ways.3 First, it expanded the reach of the protec-
tion to include any “religious exercise,” including “any exer-
cise of religion, whether or not compelled by or central to, a
system of religious belief.” 

(quoting
42 U.S.C. § 2000cc-5(7)(A)). In fact, RLUIPA “bars inquiry
into whether a particular belief or practice is ‘central’ to a
prisoner’s religion.” 

n.13; 42 U.S.C.
§ 2000cc-5(7)(A). Second, as opposed to the deferential ratio-
nal basis standard of Turner v. Safley, 

, 89-90
(1987), RLUIPA requires the government to meet the much
   3
     RLUIPA’s language closely tracks that of its predecessor, the Reli-
gious Freedom Restoration Act of 1993 (“RFRA”), which “prohibits [the]
[g]overnment from substantially burden[ing] a person’s exercise of reli-
gion even if the burden results from a rule of general applicability unless
the government can demonstrate the burden (1) is in furtherance of a com-
pelling governmental interest; and (2) is the least restrictive means of fur-
thering that compelling governmental interest.” 

-
715 (internal citations and quotation marks omitted). In City of Boerne v.
Flores, 

, 515-16 (1997), the Supreme Court invalidated
RFRA as applied to the states, because it “exceeded Congress’ remedial
powers under the Fourteenth Amendment.” 

(citing
City of 

).
864              GREENE v. SOLANO COUNTY JAIL
stricter burden of showing that the burden it imposes on reli-
gious exercise is “in furtherance of a compelling governmen-
tal interest; and is the least restrictive means of furthering that
compelling governmental interest.” 42 U.S.C. § 2000cc-
1(a)(1)-(2). See also 

; 

.

          1.   Substantial Burden/Religious Exercise

   The district court awarded summary judgment to Rourk on
Greene’s RLUIPA claim because, in the district court’s view,
denying Greene the ability to participate in group worship
would not “substantially burden his ability to exercise his reli-
gion” because he “was not required to act contrary to their
[sic] religious beliefs. Moreover . . . alternative means for
exercising his religion remained available to plaintiff.” (inter-
nal citations omitted). We disagree with the district court’s
analysis and its conclusion.

   In any RLUIPA claim, we must begin by identifying the
“religious exercise” allegedly impinged upon. Next, we must
ask whether the prison regulation at issue “substantially bur-
dens” that religious exercise.

   Rourk urges an expansive interpretation of “religious exer-
cise.” In her view, “religious exercise” is, in effect, the gen-
eral practice of one’s religion, rather than any particular
practice within one’s religion. For example, she argues that
Greene’s ability to engage in group worship is not, by itself,
his religious exercise, but rather, is one component of his reli-
gious exercise. Applying Rourk’s definition, she may, without
violating RLUIPA, impose outright bans on particular aspects
of an inmate’s religious exercise, so long as, in the aggregate,
those bans do not amount to a substantial burden.

   Rourk’s definition of “religious exercise” is supported nei-
ther by the plain language of RLUIPA, nor by the caselaw
interpreting it. As noted above, RLUIPA specifically defines
                 GREENE v. SOLANO COUNTY JAIL                865
“religious exercise” as “any exercise of religion, whether or
not compelled by, or central to, a system of religious belief.”
42 U.S.C. § 2000cc-5(7)(A) (emphasis added). In Cutter, the
Court noted that, “[T]he ‘exercise of religion’ often involves
not only the belief and profession but the performance of . . .
physical acts [such as] assembling with others for a worship
service [or] participating in sacramental use of bread and

(quoting Employment Div., Dep’t of
Human Res. of Or. v. Smith, 

, 878-82 (1990)).

   In San Jose Christian College v. City of Morgan Hill, 

(9th Cir. 2004), we considered the meaning of “re-
ligious exercise” in the context of a city’s zoning process. The
college sued the city under RLUIPA after the city denied a
zoning application which sought permission to construct “an
education facility” on land zoned for use as a hospital. 

We described the “religious exercise” as “the conver-
sion of real property for the purpose of religious exercise.” 

(quoting 42 U.S.C. § 2000cc-5(7)(B)). The analysis
turned not on whether the owners of the school could practice
their religion even without being able to construct a facility
for religious education, but whether the denial of their appli-
cation burdened a particular facet of their religious practice —
the conversion of their land for the purpose of religious exer-
cise. See also Guru Nanak Sikh Soc’y of Yuba City v. County
of Sutter, 

, 981 (9th Cir. 2006) (defining the rele-
vant religious exercise as the congregation’s construction of
a temple). Similarly, the religious exercise at issue in
Greene’s lawsuit is not his ability to practice his religion as
a whole, but his ability to engage in group worship.

   Rourk’s reliance on Warsoldier v. Woodford, 

(9th Cir. 2005), is misplaced. At issue in Warsoldier was a
prison regulation restricting the hair length of its inmates to
three inches. 

That regulation conflicted with War-
soldier’s religious belief that hair should only be cut “upon
the death of a close relative.” 

the prison
under RLUIPA. 

argued that the regulation did
866              GREENE v. SOLANO COUNTY JAIL
not burden Warsoldier’s religious practice, substantially or
otherwise, because he was not actually forced to cut his hair.

996. Rather, the prison allowed him a “choice”
between two options: he could either 1) cut his hair, or 2)
remain confined in his cell, work additional duty hours, and
receive less time credits and fewer privileges, including
expulsion from vocational classes, less recreation time, and
less money to spend at the prison store. 

this
false choice, holding that “punishments to coerce a religious
adherent to forgo her or his religious beliefs is an infringe-
ment on religious exercise.” 

(citations omitted).

   Warsoldier is principally a case about the meaning of “sub-
stantial burden,” not “religious exercise.” There is no clear
discussion about the meaning of the term “religious exercise”
and whether forcing Warsoldier to cut his hair violates his
religion as a whole or the particular aspect of his practice that
prohibits an adherent from cutting his hair except upon the
death of a close relative. Warsoldier thus provides no support
for Greene.

   [3] RLUIPA’s plain language and our caselaw interpreting
it compel the conclusion that the “religious exercise” at issue
in Greene’s lawsuit is group worship, not Christianity. Our
conclusion is in harmony with every other case of which we
are aware to have considered this issue. See 

(citing group worship as an example of religious exer-
cise); Spratt v. R.I. Dep’t of Corrs., 

, 38 (1st Cir.
2007) (relevant religious exercise was the maximum security
inmate’s ability to preach to other inmates); Baranowski v.
Hart, 

, 124 (5th Cir. 2007) (relevant religious
exercise was keeping kosher and observing the Jewish Sab-
bath); Lovelace v. Lee, 

, 187 (4th Cir. 2006) (rel-
evant religious exercise was observing Ramadan and
attending group prayer services).

   [4] Next, we must inquire into whether the prison’s prohibi-
tion on group worship constitutes a “substantial burden” on
                 GREENE v. SOLANO COUNTY JAIL                867
this religious exercise. We have little difficulty in concluding
that an outright ban on a particular religious exercise is a sub-
stantial burden on that religious exercise. See Murphy v. Mo.
Dep’t of Corrs., 

, 988 (8th Cir. 2004) (conclud-
ing that a ban on “communal worship” substantially burdened
inmate’s religious exercise, thereby precluding summary
judgment); Meyer v. Teslik, 

, 989 (W.D.
Wis. 2006) (holding that ban on group worship substantially
burdened inmate’s religious exercise and noting that, “It is
difficult to imagine a burden more substantial than banning an
individual from engaging in a specific religious practice”).

  [5] We conclude that the Claybank jail’s policy of prohibit-
ing Greene, a maximum security prisoner, from attending
group religious worship services substantially burdened his
ability to exercise his religion.

           2.   Compelling Governmental Interest

   Once a plaintiff makes the requisite showing under
RLUIPA of a substantial burden on the exercise of his reli-
gion, it becomes the defendant’s responsibility to establish
that the burden furthers “a compelling governmental interest,”
and does so by “the least restrictive means.” 42 U.S.C.
§ 2000cc-1(a); 42 U.S.C. § 2000cc-2(b); War

.

   Rourk asserted, and the district court agreed, that the policy
of precluding maximum security prisoners such as Greene
from participating in group worship served the compelling
governmental interest of maintaining prison security. Prison
security is a compelling governmental interest, 

n.13, and the district court was correct in finding
there was no dispute as to this issue. The question is whether
precluding group worship by maximum security prisoners at
the Claybank jail is the least restrictive means of furthering
this compelling governmental interest.
868              GREENE v. SOLANO COUNTY JAIL
                  3.   Least Restrictive Means

   Because disputed issues of material fact exist as to whether
the policy of prohibiting group worship by maximum security
prisoners is the least restrictive means of maintaining security
at the Claybank jail, the district court erred in granting sum-
mary judgment in favor of Rourk on Greene’s RLUIPA claim.

   [6] Rourk argued the policy was the least restrictive means
of achieving jail security for essentially two reasons. First, she
contended that the maximum security area at the Claybank
jail does not have an available classroom because there was
only one classroom in the facility, and it was located in the
minimum security area. Second, she argued that “for reasons
of prison security, inmates housed in maximum security could
not meet in a group setting.” And further that, “[j]ail security
would be severely threatened if the potentially violent offend-
ers in maximum security were not very closely supervised and
if groups of maximum security prisoners were allowed to con-
gregate outside their modules.” Rourk further stated that
Greene

      . . . has no idea of the intricacies of operating a
      prison . . . [h]e cannot seem to see the difference
      between inmates who are housed in minimum or
      medium security and those housed in maximum
      security areas . . . [he] sees an empty space [and]
      thinks he should be allowed to occupy it . . . [t]he
      inmates, however, are not allowed to run the jails,
      and those who are responsible for administering pris-
      ons must be accorded deference . . .

  [7] These assertions were contested by Greene. He pointed
out that, “[t]he law library is down the hall from maximum
security . . . [and] was available to inmates in maximum for
group worship.” He explained that he “and other maximum
security inmates were escorted to the law library classroom in
groups by the one custody staff assigned to Maxi. II at least
                GREENE v. SOLANO COUNTY JAIL                869
once a week, being there for up to two hours. When taken to
the library, we were left unattended in group settings without
incidents.”

   While Rourk is correct that prison administrators are to be
accorded deference with regard to prison security, 

, 725, she still must show that she “actually con-
sidered and rejected the efficacy of less restrictive measures
before adopting the challenged practice.” 

(“[E]ven outside the context of a minimum secur-
ity facility, [the defendant] cannot meet its burden to prove
least restrictive means unless it demonstrates that it has actu-
ally considered and rejected the efficacy of less restrictive
measures before adopting the challenged practice.”) (citing
United States v. Playboy Entm’t Group, Inc., 

,
824 (2000) (finding, in the context of a First Amendment
challenge to speech restrictions, that “[a] court should not
assume a plausible, less restrictive alternative would be inef-
fective”)).

   [8] There is a genuine issue of material fact as to whether
a total ban on group religious worship by maximum security
prisoners at the Claybank jail is the least restrictive means of
maintaining jail security. Summary judgment on this issue in
favor of Rourk was inappropriate.

   Nothing in our opinion should cast doubt on the fact that
prison officials may, under certain circumstances, substan-
tially burden a prisoner’s ability to engage in religious exer-
cise. But in light of RLUIPA, no longer can prison officials
justify restrictions on religious exercise by simply citing to
the need to maintain order and security in a prison. RLUIPA
requires more. Prison officials must show that they “actually
considered and rejected the efficacy of less restrictive mea-
sures before adopting the challenged practice.” 

. If prison officials meet that standard, the
prison regulation passes muster under RLUIPA, regardless of
the burden it imposes on religious exercise.
870             GREENE v. SOLANO COUNTY JAIL
  B.   Sua Sponte Summary Judgment on Greene’s Section
       1983 and Penal Code Section 4027 Claims

   [9] Greene alleged that the prohibition on group worship
also violated his rights under the First, Eighth, and Fourteenth
Amendments. The magistrate judge entered an order explain-
ing that Greene’s amended complaint “states a cognizable
claim for relief pursuant to 42 U.S.C. § 1983 and 28 U.S.C.
§ 1915A(b).” Rourk then moved for summary judgment.
Rourk’s Notice of Motion for Summary Judgment stated that
she was “entitled to summary judgment as a matter of law
with respect to the claim for relief under § 1983 . . . .” How-
ever, her Memorandum of Points and Authorities was dedi-
cated solely to arguing the issues of “compelling interest”/
“least restrictive means” under RLUIPA. Because Rourk did
not “either produce evidence negating an essential element
of” Greene’s section 1983 and Penal Code section 4027
claims, or show that Greene did “not have enough evidence
of an essential element to carry [his] ultimate burden of per-
suasion at trial,” Nissan Fire & Marine Ins. Co., Ltd. v. Fritz
Cos., Inc., 

, 1102 (9th Cir. 2000), summary
judgment in Rourk’s favor was not appropriate as to those
claims.

   Moreover, the district court’s summary judgment dismiss-
ing Greene’s section 1983 and Penal Code section 4027
claims was granted sua sponte. Sua sponte grants of summary
judgment are only appropriate if the losing party has “reason-
able notice that the sufficiency of his or her claim will be in
issue.” Buckingham v. United States, 

, 742 (9th
Cir. 1993). See also Evans v. United Airlines, Inc., 

, 945 (5th Cir. 1993) (where the defendant’s motion for
summary judgment did not address many of the plaintiffs’
claims, the plaintiffs were not on notice as to those claims).

   Greene’s response to Rourk’s Motion for Summary Judg-
ment laid out the standard for summary judgment and went on
to respond to Rourk’s Statement of Disputed Facts, address-
                 GREENE v. SOLANO COUNTY JAIL                 871
ing those facts that he believed were in dispute. He set forth
the legal standard under the First Amendment. He next set
forth the standard under RLUIPA. Then he went on to apply
the standard under RLUIPA with regard to “compelling
interest”/“least restrictive means” to the facts of his case and
to Rourk’s assertions. Though Greene made opaque mention
of his other claims, such mention was incidental and not a
focal point of his response.

   Greene was a pro se plaintiff. As such, he cannot be
expected to anticipate and prospectively oppose arguments
that an opposing defendant does not make. See Rand v. Row-
land, 

, 957 (9th Cir. 1998). Greene did not have
a “full and fair opportunity to ventilate the issues” prior to the
district court’s summary judgment on these claims. Cool Fuel,
Inc. v. Connett, 

, 312 (9th Cir. 1982).

  [10] Because Rourk did not meet her burden as the moving
party on summary judgment as to the section 1983 and Penal
Code section 4027 claims, and because Greene did not have
notice and an opportunity to oppose summary judgment on
those claims, summary judgment on them was inappropriate.

                        CONCLUSION

   We REVERSE the district court’s summary judgment in
favor of Rourk on Greene’s RLUIPA claim and REMAND
that claim to the district court for further proceedings. We
also VACATE the district court’s summary judgment in favor
of Rourk on Greene’s claims under 42 U.S.C. § 1983 and
Penal Code section 4027, and REMAND those claims as well
to the district court for further proceedings.

  REVERSED         in   part,   VACATED         in    part,   and
REMANDED.