N.M. Stat. § 31-18-21 (2026)

A. Whenever an inmate in a penal institution of this state or of any county therein is
sentenced for committing any felony while he is an inmate, the sentence imposed shall
be consecutive to the sentence being served, and his period of parole shall be that set
according to the provisions of Section 31-21-10 NMSA 1978.

    B. Any person, who commits a crime while at large under a suspended or deferred
sentence or probation or parole, and who is convicted and sentenced therefor, shall
serve the sentence consecutive to the remainder of the term, including remaining parole
time, under which he was released unless otherwise ordered by the court in sentencing
for the new crime.

History: 1953 Comp., § 40A-29-34, enacted by Laws 1977, ch. 216, § 10.

                                     ANNOTATIONS

Intent of legislature. — Construing Subsection A of this section together with the other
sentencing statutes in the Criminal Sentencing Act leads to the inescapable conclusion
that the legislature intended to impose harsher and more certain punishment on inmates
who commit crimes while incarcerated. State v. Davis, 2003-NMSC-022, 134 N.M. 172,
74 P.3d 1064.

The legislature intended sentencing courts to stack the sentences of inmates who are
convicted of crimes while incarcerated. State v. Davis, 2003-NMSC-022, 134 N.M. 172,
74 P.3d 1064.

Prison disciplinary measures do not bar subsequent prosecution in a criminal
action for violation of a penal statute prohibiting the same act which was the basis of the
person's discipline. Washington v. Rodriguez, 1971-NMCA-021, 82 N.M. 428, 483 P.2d
309.

Consecutive sentences proper. — Court may, at its discretion, impose consecutive
sentences. State v. Frederick, 1964-NMSC-045, 74 N.M. 42, 390 P.2d 281.

Modification of sentences in parole revocation. — In a parole revocation, the court
may only modify an existing sentence. When the existing sentence is consecutive to a
previous sentence, the court may make the existing sentence concurrent because doing
so does not increase the sentence. However, the court may not change a sentence that
was originally concurrent to be consecutive because doing so would increase the
sentence. In a first sentence, however, Subsection B of Section 31-18-21 NMSA 1978 is
never applicable and the sentence cannot be made concurrent or consecutive with a
later sentence as a result of probation violation because for a first sentence there is no
concurrent or consecutive status to be modified. To hold otherwise would allow
probation revocations for previous convictions to undermine concurrent or consecutive
sentences for later convictions. State v. Rapchack, 2011-NMCA-116, 150 N.M. 716, 265
P.3d 1289, cert. denied, 2011-NMCERT-010.

Subsection B of Section 31-18-21 NMSA 1978 applies to sentences as originally
imposed. The order of probation revocation does not change the character or original
order of the sentences. State v. Rapchack, 2011-NMCA-116, 150 N.M. 716, 265 P.3d
1289, cert. denied, 2011-NMCERT-010.

Modification of multiple sentences in parole revocation. — Where defendant
pleaded guilty to burglary of a vehicle and the first judge suspended defendant’s
sentence; defendant subsequently pleaded guilty to auto-theft related crimes before a
second judge and the second judge suspended defendant’s sentence and ordered the
sentence to be served consecutive to the sentence in the burglary case; defendant was
later arrested for a third crime; in 2008, the second judge revoked defendant’s probation
in the auto-theft case; in 2009, first judge revoked defendant’s probation in the burglary
case and ordered that the sentence in the burglary case be served concurrently with the
sentence in the auto-theft case; and the first judge later corrected the order to state that
the sentence in the burglary case would not run concurrently with the sentence in the
auto-theft case, the order making the sentence in the burglary case concurrent with the
sentence in the auto-theft case was contrary to law and the first judge had the power to
correct the order, because the sentence in the burglary case was the first sentence, the
first sentence could not originally have been concurrent with or consecutive to anything
and could not be modified to become concurrent or consecutive. State v. Rapchack,
2011-NMCA-116, 150 N.M. 716, 265 P.3d 1289, cert. denied, 2011-NMCERT-010.

Sentencing judge has no discretion under this section regarding whether a sentence
is to be served consecutively or concurrently. The legislature’s use of the word "shall" in
Subsection A makes consecutive sentencing mandatory. State v. Davis, 2003-NMSC-
022, 134 N.M. 172, 74 P.3d 1064.
Section alters common-law rule. — The common-law rule is that in the absence of
statute two or more sentences are to be served concurrently unless otherwise ordered
by the court. This section alters the common-law rule only as to crimes committed while
at large under a sentence for a prior crime. Deats v. State, 1972-NMCA-155, 84 N.M.
405, 503 P.2d 1183.

Unless court orders otherwise, section postpones stated beginning date of new
sentence until the prior sentence is completed. Herring v. State, 1969-NMCA-117, 81
N.M. 21, 462 P.2d 468.

Beginning date of sentence. — Sentence imposed upon defendant while he was on
parole from prior sentence ran consecutive to prior sentence although trial court stated
beginning date for new sentence but did not order that it run concurrently with prior
sentence. Herring v. State, 1969-NMCA-117, 81 N.M. 21, 462 P.2d 468.

Although the beginning date of the new sentences imposed following conviction of
forgery was stated in the commitment of defendant on parole, that beginning date was
postponed by this section where the trial court did not order otherwise; further, the
record showed that the court did not intend the sentences for the three forgeries to run
concurrently with any other sentence imposed upon defendant. State v. Upshaw, 1968-
NMCA-070, 79 N.M. 484, 444 P.2d 995.

Effect of return of defendant to penitentiary before trial. — Defendant's assertion
that the district court lost jurisdiction over him because he was "released" to the
penitentiary for parole violation before being tried did not raise any issue of illegality.
The parole authorities could revoke defendant's parole and return him to the
penitentiary for a parole violation, and this section clearly contemplates the conviction
and sentence of a person for a crime committed while at large under parole. State v.
Ford, 1970-NMCA-061, 81 N.M. 556, 469 P.2d 535.

"Presentence" confinement credit not allowed. — This section mandates that a
sentence for a felony committed while serving a sentence in a penal institution run
consecutive to the prior sentence. It is impossible to grant "presentence" confinement
credit concurrent with time served on the prior sentence and comply with this section,
which requires that the sentences run consecutively. State v. Facteau, 1990-NMSC-
040, 109 N.M. 748, 790 P.2d 1029.

Discretionary award of presentence confinement credit for offense committed
while on probation. — Since defendant was outside of a penal institution on parole
when he committed a second offense (possession of drug paraphernalia), the
sentencing judge had discretion under Subsection B to make defendant's sentence run
concurrent or consecutive to any sentence defendant was then serving for a parole
violation, including the authority to award presentence confinement credit on the facts of
the case. State v. Irvin, 1992-NMCA-121, 114 N.M. 597, 844 P.2d 847.
Law reviews. — For article, "The Proposed New Mexico Criminal Code," see 1 Nat.
Resources J. 122 (1961).

Am. Jur. 2d, A.L.R. and C.J.S. references. — Sentencing for new offenses committed
while accused was on parole or conditional release as concurrent or consecutive, 116
A.L.R. 811.