United States Court of Appeals
                             For the Eighth Circuit
                         ___________________________

                                 No. 16-4225
                         ___________________________

                                    Pedro Guzman

                        lllllllllllllllllllllPetitioner - Appellant

                                            v.

                                Larry Denney, Warden

                       lllllllllllllllllllllRespondent - Appellee
                                       ____________

                     Appeal from United States District Court
                  for the Western District of Missouri - St. Joseph
                                  ____________

                               Submitted: June 1, 2017
                                 Filed: July 6, 2017
                                   [Unpublished]
                                   ____________

Before WOLLMAN, BOWMAN, and KELLY, Circuit Judges.
                       ____________

PER CURIAM.

      Missouri prisoner Pedro Guzman appeals the district court’s order denying his
28 U.S.C. § 2254 petition challenging his Missouri conviction for first-degree assault.
We grant a certificate of appealability, vacate the district court’s judgment, and
remand for further proceedings. See Slack v. McDaniel, 

, 478 (2000)
(COA requirements).
       Guzman claimed in his section 2254 petition that, during the plea-bargaining
process in his state criminal proceedings, trial counsel provided ineffective assistance
by incorrectly advising him that the victim’s injuries were not severe enough to
support a conviction for second-degree assault. Guzman rejected an offer to plead
guilty to second-degree assault and receive a five-year prison sentence. Thereafter,
the State amended the charge to first-degree assault; Guzman eventually pleaded
guilty to this charge and was sentenced to 25 years in prison.

       The district court correctly determined that Guzman had procedurally defaulted
his claim because his counsel omitted it from his state post-conviction motion. See
Mo. Sup. Ct. R. 24.035 (motion must include every claim known, and movant shall
declare that all known claims are listed and that all other known claims are waived).
We conclude, however, that the default is excused, because post-conviction counsel
erroneously omitted a claim with “some merit.” See Martinez v. Ryan, 

,
14 (2012) (ineffective assistance in state collateral proceeding may establish cause
for default of trial-related ineffective-assistance claim, if state law requires such
claims to be presented in collateral proceeding, and if trial-related ineffective-
assistance claim has “some merit”); Arnold v. Dormire, 

, 1088 (8th Cir.
2012) (because Missouri practice provides that movants must wait until post-
conviction proceeding to raise claims of ineffective assistance of trial counsel,
movants can raise Martinez error to excuse default by post-conviction counsel).

       Specifically, the state-court record includes evidence that trial counsel told
Guzman that the State would have difficulty proving second-degree assault, because
the victim’s injuries did not amount to “serious physical injury.” See Mo. Rev. Stat.
§ 565.060 (2000) (person commits second-degree assault if he or she, inter alia,
knowingly causes or attempts to cause serious physical injury to another person under
influence of sudden passion arising out of adequate cause, or recklessly causes
serious physical injury to another person). Evidence that was available to trial
counsel at the time, however, showed that as a result of Guzman’s punch, the victim

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momentarily lost consciousness, and suffered a broken jaw and three chipped teeth.
Advice that this was insufficient to show “serious physical injury” would have been
erroneous, and below an objective standard of reasonable competence. See Nave v.
Delo, 

, 1035 (8th Cir. 1995) (counsel’s performance is constitutionally
deficient if it falls below objective standard of reasonable competence); Mo. Rev.
Stat. § 565.002(6) (2000) (“serious physical injury” includes physical injury that
causes protracted impairment of the function of any part of the body); State v.
Mentola, 

, 421-22 (Mo. Ct. App. 1985) (fracture of jaw preventing
victim from chewing food for 6 weeks was “protracted loss or impairment”; noting
8 days could be “protracted” period).

       We remand for further proceedings to determine whether Guzman can show he
was prejudiced by counsel’s erroneous advice, because it influenced his decision to
reject the five-year plea offer. We note that other reasons that also may have
influenced Guzman’s decision to reject the plea offer do not necessarily preclude him
from showing that counsel’s erroneous advice was a motivating factor in the decision.
                       ______________________________




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