United States Court of Appeals
                      For the First Circuit

No. 08-2458

                    JOSE JULIAN CRUZ BERRÍOS,

                      Plaintiff, Appellant,

                                v.

   CARLOS GONZÁLEZ-ROSARIO, WILLIAM CLASS-QUIRÓS, RAFAEL OLIVER
    BAEZ, MIGUEL ORTIZ-MARRERO, ENIL MONTALVO-MORALES, SANTOS
        JIMÉNEZ-COLÓN, ERICK GARCÍA-SANTOS, EDDIE M. CRUZ-
      SANTIAGO,SERGEANT UZZIEL RUIZ-LEDEÉ, SERGEANT REINALDO
  SURÉN,SERGEANT OSVALDO RIVERA-DOMÍNGUEZ, FNU O'FARRILL, JAMIE
  LÓPEZ, JORGE SILVESTRINI, JORGE RODRÍGUEZ, MIGUEL PEREIRA and
                         WILMER SEPÚLVEDA,

                      Defendants, Appellees.


          APPEAL FROM THE UNITED STATES DISTRICT COURT
                 FOR THE DISTRICT OF PUERTO RICO

         [Hon. Francisco A. Besosa, U.S. District Judge]


                              Before

                       Lynch, Chief Judge,
               Boudin and Howard, Circuit Judges.


     Victor J. Quiñones, Edgardo Cartagena, Ramon E. Dapena and
Usera Morell Bauza Dapena & Cartagena, LLP, on brief for appellant.
     Irene S. Soroeta-Kodesh, Solicitor General, Leticia Casalduc-
Rabell, Deputy Solicitor General, Zaira Z. Girón-Anadón, Deputy
Solicitor General, and Michelle Camacho-Nieves, Assistant Solicitor
General, Department of Justice, on brief for appellees.



                        December 16, 2010
            HOWARD, Circuit Judge.     José Julian Cruz-Berríos, an

inmate currently serving a sentence under the jurisdiction of the

Puerto Rico Department of Corrections, brought a federal civil

rights action against various corrections officers whom he alleges

exerted excessive force against him.    The district court dismissed

the action after determining that it was precluded as res judicata

by his previous, unsuccessful state suit based on similar alleged

conduct.1   Cruz-Berríos v. Gonzalez-Rosario, 

(D.P.R. 2008).   Cruz-Berríos now appeals.   After review, we affirm

in part, reverse in part, and remand the case to the district court

for further development of the record and clarification on matters

of Puerto Rico law.



                                  I.

            In March 2004, Cruz-Berríos filed a lawsuit in the Puerto

Rico Court of First Instance under Article 1802 of the P.R. Civil

Code, P.R. Laws Ann. tit. 31 § 5141, alleging that officers in the

Puerto Rico correctional facility where he was housed had assaulted

him in retaliation for implicating them in a drug trafficking

investigation. His complaint referred to two separate incidents of

abuse, one on November 9, 2002, and another on February 28, 2004.


     1
      Puerto Rico is the functional equivalent of a state for all
purposes relevant to this case.    Accordingly, we refer here to
state actions and state courts, notwithstanding Puerto Rico's
unique commonwealth status. See, e.g., R.G. Fin. Corp. v. Vergara-
Nunez, 

, 183 n.2 (1st Cir. 2006).

                                 -2-
                Shortly after initiating that action, Cruz-Berríos also

filed a complaint in federal district court under 42 U.S.C. § 1983,

making similar allegations.                  Some, though not all, of the named

defendants in the federal complaint were also defendants in the

state        court    case.       Cruz-Berríos      twice   amended     the   federal

complaint, each time adding a new incident that he claimed had

occurred after the most recent filing.2                     In the first amended

complaint,           he   added     additional      corrections        officers    and

administrators as defendants and included a third assault that had

allegedly occurred on August 18, 2004, which he claimed was part of

the   same      general       pattern   of    retaliation   as   the    original   two

incidents.           In the second amended complaint, he alleged a fourth

such incident, which he claimed occurred on March 2, 2005, and

added another prison administrator as a defendant.3                    Of these four

alleged incidents, only the claims concerning the last three were

permitted to proceed, as the district court determined that the

claim arising out of the November 2002 incident was time-barred.4

                Due to developments in the state court case, however,

those three claims did not proceed very far.                 After a bench trial,


        2
            At no point did Cruz-Berríos amend his state complaint.
      3
      In order to avoid a sovereign immunity bar, he also specified
that any claims for damages were against the defendants in their
personal capacities, while any injunctive relief sought was against
the defendants in both their personal and official capacities. See
Edelman v. Jordan, 

, 664–65 (1974).
        4
            Cruz-Berríos does not challenge this conclusion on appeal.

                                              -3-
the Court of First Instance entered judgment against Cruz-Berríos,

finding that no excessive use of force had been used on either of

the dates discussed in the state complaint (November 2002 and

February 2004) and that he had failed to show that he had been

singled out for retaliatory persecution or harassment.         That

adverse judgment, the federal district court later held, precluded

the § 1983 action in its entirety, including the allegations

against the additional defendants concerning incidents that had not

previously been the subject of litigation.     The district court

dismissed the case, and this appeal ensued.



                                II.

          The defendants ask us to affirm on two separate bases.

They primarily argue that we may rely on the district court's

preclusion rationale, which is subject to de novo review.   Ramallo

Bros. Printing, Inc. v. El Dia, Inc., 

, 89 (1st Cir.

2007).   Offering an alternative means to the same end, they also

assert that Cruz-Berríos failed to exhaust his administrative

remedies before filing his federal claim, in violation of 42 U.S.C.

§ 1997e(a).   Because the second of these arguments may provide an

uncomplicated means of resolving this case on a more developed

record, we begin there.




                                -4-
                                   A.

           The Prison Litigation Reform Act of 1995 ("PLRA"), 42

U.S.C. § 1997e(a), provides that "[n]o action shall be brought with

respect to prison conditions under section 1983 of this title, or

any other Federal law, by a prisoner confined in any jail, prison,

or other correctional facility until such administrative remedies

as are available are exhausted."           This exhaustion requirement

applies to allegations of physical violence by prison guards.

Porter v. Nussle, 

, 532 (2002).

           The defendants contend that dismissal is warranted here

because the complaint fails to indicate whether or not Cruz-Berríos

has exhausted his administrative remedies.        But it was not Cruz-

Berríos's burden to plead exhaustion, which must be raised and

proved by the defense.      Jones v. Bock, 

, 216 (2007).

Although the defendants have now raised the issue, neither they nor

Cruz-Berríos have pointed to any evidence in the record that would

indicate one way or the other whether the exhaustion requirement

has in fact been satisfied.            And because the district court

dismissed the case on preclusion grounds, it never addressed the

matter.   Accordingly, we remand the case to the district court for

additional   fact-finding    as   to    whether   the   PLRA   exhaustion

requirement bars Cruz-Berríos's suit or not.            If so, it would

obviate any further need to consider the preclusive effect of the




                                  -5-
Court of First Instance's decision.           But this is the defendants'

burden to prove.



                                    B.

          A   final    judgment     on    a    matter   may,   in   certain

circumstances,     prevent   that   matter's      re-adjudication    in   a

subsequent case. The doctrine of res judicata5 "relieve[s] parties

of the cost and vexation of multiple lawsuits, conserve[s] judicial

resources, and, by preventing inconsistent decisions, encourage[s]

reliance on adjudication."        Allen v. McCurry, 

, 94

(1980).   Because "[u]nder the full faith and credit statute, 28

U.S.C. § 1738, a judgment rendered in a state court is entitled to

the same preclusive effect in federal court as it would be given

within the state in which it was rendered," In re Sonus Networks,

Inc., 

, 56 (1st Cir. 2007), we look to Puerto Rico law

in order to determine the res judicata implications of the Court of

First Instance's judgment.

          Puerto Rico's law of res judicata is codified at P.R.

Laws Ann. tit. 31, § 3343, which provides that a prior judgment


     5
      Depending on the speaker's intention, the term "res judicata"
may refer either to the doctrine of claim preclusion specifically
(coupled with "collateral estoppel" as a synonym for issue
preclusion) or else to the doctrines of claim and issue preclusion
collectively. We here use the phrase in the second sense. See
Taylor v. Sturgell, 

, 2170 n.5 (2008) (explaining
that the broad meaning of res judicata as an umbrella term that
encompasses both claim preclusion and issue preclusion "ha[s]
replaced a more confusing lexicon").

                                    -6-
will       have    preclusive       effect    when    there     is    "the    most      perfect

identity between the things, causes, and persons of the litigants,

and their capacity as such."                  This provision encompasses both of

the two traditional aspects of res judicata:                         claim preclusion and

issue preclusion.               Coors Brewing Co. v. Mendez-Torres, 

,

19 (1st Cir. 2009). Under Puerto Rico's res judicata scheme, claim

preclusion "binds parties from litigating or relitigating any claim

that was or could have been litigated in a prior adjudication and

prevents claim splitting," Gener-Villar v. Adcom Group, Inc., 

, 205 (1st Cir. 2005) (per curiam) (internal brackets

omitted);          issue    preclusion,       on     the    other     hand,       "forecloses

relitigation         in    a     subsequent    action      of   a    fact    essential     for

rendering a judgment in a prior action between the same parties,

even when different causes of action are involved." 

                  The three claims presented to us on appeal, corresponding

to the final three alleged incidents of abuse, fall into two

categories.6             The February 2004 incident has already been the

subject of actual litigation in the Court of First Instance.                               The

August 2004 and March 2005 incidents, on the other hand, have not.

The district court concluded that this distinction was irrelevant

and that all three claims were subject to issue preclusion. Citing

the    rule       that     "a    plaintiff    cannot       avoid     the    bar    of   [issue


       6
      Cruz-Berríos claimed four separate incidents of abuse in his
second amended complaint, but because the first of these claims was
time-barred, our review extends only to the final three.

                                              -7-
preclusion] simply by suing a defendant for continuing the same

conduct that was found to be lawful in a previous suit brought by

the same plaintiff,"7       Ramallo Bros. Printing, 

, the court held that no material differences existed between any

of the alleged incidents of abuse because the plaintiff presented

them as part of a "continuing pattern of violation." 

(emphasis in original).           As a result, to the

extent that the first set of incidents was found to be lawful in

the state case, the second set of incidents would also be lawful as

a matter of issue preclusion.

           We disagree.        The distinction between the claims already

adjudicated and those not already adjudicated remains critical

here.    It     is   therefore    necessary    to   unravel   the   individual

allegations that the district court viewed as part of a single

whole.



                                       1.

           To begin with, issue preclusion does not apply to the

events   that    the   Court    of   First   Instance   never   expressly   or

implicitly considered.          The alleged August 2004 and March 2005


     7
      Cruz-Berríos correctly observes that this principle is taken
from a case concerning federal, rather than Puerto Rico, issue
preclusion principles. He does not, however, offer any authority
one way or the other as to whether Puerto Rico law encompasses an
analogous rule. Because we ultimately conclude that the principle
is inapposite to this situation anyway, we will assume without
deciding that Puerto Rico law mirrors federal law on this point.

                                       -8-
beatings, which appeared for the first time in the federal case,

are independent events that are far too fact-specific to lend

themselves to generalization as "the same conduct" examined in the

state case.       That the Court of First Instance held Cruz-Berríos's

treatment in prison to be lawful on certain occasions does not

necessarily dictate as a matter of issue preclusion that his

treatment on subsequent occasions must be held lawful as well. Cf.

Dawkins v. Nabisco, Inc., 

, 397 (5th Cir. 1977)

(holding under federal res judicata principles that a dismissal of

a   Title   VII    retaliation   claim   could      not    preclude     claims    of

subsequent retaliation because otherwise "a company that had once

won a suit alleging retaliation for participation in Title VII

proceedings would be free to retaliate at will against the earlier

plaintiff     without    fear    of   being    held       accountable    for     its

actions."). At this juncture, it is impossible to tell whether the

conduct newly alleged in the federal case would turn out to be

meaningfully different from the conduct tried on the merits in the

state   case.       Further   proceedings     may   establish    that     the    new

allegations are simply more of the same, or they may turn out to be

something more egregious.

            The defendants argue that insofar as Cruz-Berríos has

chosen to present the individual incidents as part of a continuing

pattern of abuse, the issue posed by the new claims is actually

identical to the one already adjudicated in state court.                         The


                                      -9-
response is that this is not necessarily so.                      It discounts the fact

that there are two more alleged incidents of beatings later.                                It

also discounts the possibility that Cruz-Berrios's rights were

violated in at least one instance, creating potential liability for

at least some defendants regardless of whether there is a pattern.

                  At the same time, even if issue preclusion does not

apply       to    these        newly    alleged       incidents,      claim       preclusion

nevertheless might apply.                 The district court indicated that Cruz-

Berríos should have amended his state complaint to reflect these

two new incidents, which arose before his state case went to

trial.8      

.                    The court did not

indicate         the   source      of   this    rule,    and    while    the      defendants

understandably defend it on appeal, they similarly provide no

authority for it.            It is true that some jurisdictions employ a rule

that a party is obligated, on pain of preclusion, to amend a

complaint to reflect events that postdate the commencement of the

action.      See, e.g., Monterey Plaza Hotel Ltd. P'ship. v. Local 483

of Hotel Employees, 

, 928 (9th Cir. 2000) (applying

California         law      that   "the     doctrine    of     res   judicata      bars    the

relitigation           of   all    events    which     occurred      prior   to    entry    of

judgment,        and     not    just    those    acts    that     happened     before      the



        8
      Although the district court portrayed this as a matter of
issue preclusion, we think it is actually one of claim preclusion,
which, unlike issue preclusion, can bar a matter that has not yet
been actually litigated.

                                               -10-
complaint was filed."). But other jurisdictions do not impose such

a burden on plaintiffs, see, e.g., Doe v. Allied-Signal, Inc., 

, 915 (7th Cir. 1993), and there is no reason to assume

conclusorily what Puerto Rico's rule may be.    Because this issue

has not yet been briefed, we think it best to remand the case to

the district court, where the parties may have a chance to argue

whether Puerto Rico law would apply claim preclusion to post-

complaint events that could have been but were not raised through

an amended complaint.



                                2.

          We turn then to the preclusion of the federal claim

concerning the February 2004 incident, which the Court of First

Instance did adjudicate on the merits.   Cruz-Berríos contends that

this claim was not precluded, notwithstanding the state court's

adjudication of the same facts, because the res judicata statute's

requirements of "perfect identity between the things, causes, and

persons of the litigants" have not been met.   For the most part at

least, he is mistaken.    As we shall explain, an underdeveloped

record prevents us from making a less qualified statement.



                                i.

          Cruz-Berríos sued all of the federal action defendants in

both their official and personal capacities.    We can immediately


                               -11-
resolve the official-capacity claim.              Cruz-Berríos first posits

that the parties are not identical inasmuch as his federal action

contains   new     defendants.        Yet   the   Puerto     Rico    res   judicata

statute's "perfect identity of parties" clause does not demand a

literal identity; it operates, rather, as a privity requirement.

R.G. Fin. Corp. v. Vergara-Nunez, 

, 185–86 (1st Cir.

2006); Perez-Guzman v. Gracia, 

, 234 (1st Cir. 2003).

This means that the clause is satisfied whenever "one party acts

for or stands in the place of another in relation to a particular

subject matter," R.G. Fin. 

, or, in the

Puerto Rico Supreme Court's words, whenever those parties amount to

the same "party really interested."               Puerto Rican Independence

Party v. Commonwealth Elections Comm'n, 

,

632 (1988).

            That    condition    is    satisfied     here.          Traditionally,

"[t]here is privity between officers of the same government so that

a judgment in a suit between a party and a representative of the

[government] is res judicata in relitigation of the same issue

between    that    party   and   another      officer   of    the     government."

Sunshine Anthracite Coal Co. v. Adkins, 

, 402–03

(1940); see also Barclay v. Lowe, 

, 779 (2d Cir.

2005) (applying the privity principle to state corrections officers

sued in their official capacities for allegedly assaulting an

inmate).    As stated, Puerto Rico law treats such privity between


                                       -12-
parties as identity.       With respect to the plaintiff's official-

capacity   claim   based   on   the    February    2004   allegations,   the

representative roles of the defendants in this action are the same

as those in the state action. The parties in the official-capacity

suit are therefore perfectly identical to the parties in the prior

litigation.   See Del Carmen Tirado v. Dep't of Educ., 

127, 134 (D.P.R. 2003) (noting that official-capacity claims

against officers in the Puerto Rico Department of Education were

barred by res judicata, notwithstanding those officers' nonparty

status in a prior state suit).

           Cruz-Berríos next avers that the "things" and "causes"

are not identical because his federal claim arises under § 1983,

while his state claim arose under a state tort statute.          As we have

discussed elsewhere, this sort of argument "mistakes the legal

cause of action for the factual 'cause' contemplated by Puerto

Rico's preclusion statute:      preclusion requires an identity of the

latter, not the former." Baez-Cruz v. Municipality of Comerio, 

, 30 (1st Cir. 1998).     Thus, regardless of the legal vehicle

through which an action is brought, claims share a perfect identity

of cause "when they flow from the same principal ground or origin."

R.G. Fin. 

.            So long as the claims "either

were or could have been asserted in a prior action" based on the

same transaction, they are precludable.            

actions share an identity of 'things' if a decision in the second


                                      -13-
action might function to contradict a right arisen or arising from,

or a right affirmed by a prior decision."           

and quotation marks omitted).        Accordingly, "a mere difference in

the legal theories on which two causes of action are grounded does

not destroy the identity of thing or cause that otherwise exists

between two suits arising out of a common nucleus of operative

fact."    

   This all amounts to what is known in common

law   jurisdictions     as   the   "transactional     approach"      to    claim

preclusion.    

            Here,   Cruz-Berríos's    federal   claim     entails    the    same

factual cause as was dealt with in the analogous claim in his state

suit, namely, the officers' conduct on February 28, 2004; the

§ 1983 theory of liability could have originally been raised in his

state suit, Acevedo v. Srio. Servicios Sociales, 12 P.R. Offic.

Trans. 317 (1982); and a finding of liability in his federal suit

would    necessarily    contradict    the   Court    of   First     Instance's

determination that the corrections officers acted lawfully.                  The

thing and cause, like the identity of the parties, are identical.

Thus, Cruz-Berríos's state suit precludes his current official-

capacity claim against the defendants concerning the events in

February 2004.




                                     -14-
                                   ii.

          Cruz-Berríos's personal-capacity claim, on the other

hand, is not so neatly resolved.         Although the capacity in which

the defendants are sued does not affect the identities of thing and

cause, there is some possibility that it would affect the identity

of the parties.   At the outset, we note our skepticism that Puerto

Rico law would allow a plaintiff who lost against one defendant to

then bring a new claim against another defendant (to say nothing of

a claim against the same defendant merely in a different capacity)

based on the same transaction where the outcome in the first case

effectively   negates   the    claim     in   the   second.     Were   such

relitigation permissible, a plaintiff could in principle have as

many bites of the apple as there were non-privy defendants to be

sued.   This is precisely the sort of outcome that defensive non-

mutual issue preclusion typically guards against.

          At the same time, we are not in a position to convert

that instinctive skepticism into an authoritative statement that

Puerto Rico law would dispense with its mutuality requirement under

these circumstances.    So far as we can glean, the case law does not

definitively foreclose the possibility that Puerto Rico would

require mutuality even under these circumstances.             We therefore

proceed with caution, and will await further development of the

case, before making any definitive statement as to which result

Puerto Rico law intends.      On remand, the parties and the district


                                  -15-
court should devote some attention to this issue if it proves

necessary to resolve the case.

           If the personal-capacity claims are indeed subject to

non-mutual issue preclusion, then the February 2004 claim would be

barred as to all defendants, and nothing more need be said.          If, on

the other hand, it turns out that a mutuality requirement does

prevent   preclusion   against   such    newly   named   personal-capacity

defendants, we would need to take the further step of looking to

see who was named in the state suit.            It is clear that at least

some of the newly named defendants were included in the federal

complaint solely because of the August 2004 and March 2005 claims.9

Subject to our earlier discussion of post-complaint events, the

Court of First Instance's decision would not appear to preclude

those claims against those defendants.10

           Thus, a strict mutuality requirement would necessitate a

complete tally of who was named in the first suit.          Unfortunately,

the record before us contains none.          Its only reference to the

parties   before   the   Court   of     First    Instance   occurs   in   a


     9
      So far as we can tell from our reading of the second amended
complaint, these defendants are:     William Class-Quirós, Santos
Jiménez-Colón, Eddie M. Cruz-Santiago, Erick García-Santos, Enil
Montalvo-Morales, Osvaldo Rivera-Domínguez, and Wilmer Sepúlveda.
     10
      This conclusion, which follows from Puerto Rico's "identity
of parties" requirement, seems inconsistent with the extension of
res judicata to post-complaint events, even those involving
nonparties, as the district court appears to have assumed. But we
leave it to the litigants and the district court on remand to
consider in the first instance what the actual state of the law is.

                                  -16-
nonexhaustive list appearing in a Puerto Rico appeals court's

recitation of facts in the underlying case.       Although the list

mentions some defendants by name, it also adds the cryptic phrase

"and others."11   Because we cannot divine the identity of those

others, we can only speculate as to who may be shielded by res

judicata and who may not.       At the very least, any individual

clearly named as a personal-capacity defendant in the state case

would be able to preclude Cruz-Berríos's claim concerning the

events of February 2004.12   Any other individual who wishes to reap

the benefit of claim preclusion would have the opportunity on

remand to present the district court with evidence that he, too,

was a personal-capacity defendant in the state case.13      On this


     11
      It is possible that this phrase was meant as a John Doe–style
placeholder for as-yet unidentified defendants. If so, then it
would raise a question as to whether res judicata principles would
allow Cruz-Berríos for the first time in his federal complaint to
fill in who these "others" were.     We have previously expressed
doubt that a party's presence as a John Doe defendant in one suit
would preclude subsequent claims against it as a named party in a
future suit, see Iantosca v. Step Plan Servs., Inc., 

,
30 (1st Cir. 2010), but the question would ultimately be governed
by Puerto Rico law, which might have a different take.       In any
case, because the reference to "others" could easily mean named
defendants, rather than John Does, the question may yet turn out to
be academic.
     12
      These defendants are Carlos González-Rosario, Miguel Pereira,
Uziel Ruiz-Ledée, and Reinaldo Surén.
     13
      To the extent that a personal-capacity defendant in the
federal suit was named only as an official-capacity defendant in
the state action, we again defer a definitive ruling. Some courts
have found privity elastic enough to be asserted defensively by a
government official who, after prevailing in an official capacity,
is later sued personally. See 18A Charles Alan Wright, Arthur R.

                                -17-
issue, like exhaustion under the PLRA, the defense bears the burden

of proof.      Perez-Guzman v. Garcia, 

, 234 (1st Cir.

2003).   But we stress again that all of this becomes necessary only

if   Puerto    Rico's   "identity   of   parties"   rule   would   not   allow

defensive non-mutual issue preclusion on these facts.



                                    III.

              In summary, our holding varies by claim, by defendant,

and by capacity.        First, we remand for the district court to

consider whether Cruz-Berríos failed to exhaust all administrative

remedies available to him before initiating his federal action.

Resolution of that issue has the potential to dispose of the entire

action without need for further consideration of the res judicata

questions.

              As to the February 28, 2004, incident, we affirm the

district court's dismissal of the official-capacity claim against

all defendants; we also affirm the district court's dismissal of

the personal-capacity claim against those defendants already named

as personal-capacity defendants in the state case; but as to the

personal-capacity claim against those defendants whose party status

in the state case remains unclear, we reverse the dismissal and



Miller & Edward H. Cooper, Federal Practice and Procedure § 4458,
at 570-71 & n.21 (2d ed. 20002). But this question must be decided
under Puerto Rico law and is thus another matter for attention in
the district court in the first instance, if necessary.

                                    -18-
remand for such further consideration as this opinion requires.

Similarly, as to the claims concerning the events of August 18,

2004, and March 2, 2005, we reverse the dismissal and remand so

that the district court may, again depending on the resolution of

the exhaustion issue, consider whether Puerto Rico law would

preclude claims arising out of post-complaint events that could

have been but were not incorporated into the state case through an

amended complaint.

          Each party shall bear its own costs of appeal.



So ordered.




                              -19-