    Nebraska Advance Sheets
430	289 NEBRASKA REPORTS



   In conclusion, we agree with the district court that inso-
much as § 29-4106(2) forfeits Shepard’s past and future good
time and recalculates his parole eligibility and mandatory
discharge dates without regard to any good time, it violates
the constitutional prohibitions against ex post facto laws.
Shepard, at the time of his crimes, expected to automati-
cally incur good time simply through good conduct, and he
expected to have his mandatory discharge date calculated upon
his maximum sentence minus good time. Section 29-4106(2),
by allowing for forfeiture of more good time than could have
been forfeited before and by allowing for forfeiture based on
conduct that is something less than flagrant and serious mis-
conduct—indeed, conduct not even contemplated at the time
of Shepard’s crimes—substantially altered the punitive conse-
quences attached to his crimes.
                     VI. CONCLUSION
   For the foregoing reasons, we affirm the judgment of the
district court.
                                                Affirmed.



               In   re I nterest of
                            Nathaniel M., a child
                                     18
                             years of age.
                           under
    Nebraska Department of Health and Human Services,
            appellant, v. State of Nebraska and
                  Nathaniel M., appellees.
                                   ___ N.W.2d ___

           Filed November 7, 2014.      Nos. S-13-1066 through S-13-1068.

 1.	 Moot Question: Jurisdiction: Appeal and Error. Because mootness is a jus-
     ticiability doctrine that operates to prevent courts from exercising jurisdiction,
     an appellate court reviews mootness determinations under the same standard of
     review as other jurisdictional questions.
 2.	 ____: ____: ____. When a jurisdictional question does not involve a factual
     dispute, its determination is a matter of law, which requires an appellate court to
     reach a conclusion independent of the decisions made by the lower courts.
 3.	 Statutes: Appeal and Error. Statutory interpretation is a question of law that an
     appellate court resolves independently of the trial court.
                         Nebraska Advance Sheets
	                      IN RE INTEREST OF NATHANIEL M.	431
	                              Cite as 289 Neb. 430

 4.	 Moot Question: Words and Phrases. A moot case is one which seeks to deter-
     mine a question which does not rest upon existing facts or rights, in which the
     issues presented are no longer alive.
 5.	 Moot Question. The central question in a mootness analysis is whether changes
     in circumstances that prevailed at the beginning of litigation have forestalled any
     occasion for meaningful relief.
 6.	 Moot Question: Appeal and Error. An appellate court may choose to review
     an otherwise moot case under the public interest exception if it involves a matter
     affecting the public interest or when other rights or liabilities may be affected by
     its determination. This exception requires a consideration of the public or private
     nature of the question presented, the desirability of an authoritative adjudication
     for future guidance of public officials, and the likelihood of future recurrence of
     the same or a similar problem.

  Appeals from the County Court for Madison County: Ross
A. Stoffer, Judge. Appeals dismissed.
  Neleigh N. Boyer, Special Assistant Attorney General, for
appellant.
   Gail Collins, Deputy Madison County Attorney, for appellee
State of Nebraska.
    Brad Ewalt, of Ewalt Law Office, for appellee Nathaniel M.
  Wright, Connolly, Stephan, McCormack, Miller-Lerman,
and Cassel, JJ.
   P er Curiam.
   In these consolidated appeals, the Nebraska Department of
Health and Human Services (the Department) appeals from
orders of the county court for Madison County, sitting as a
juvenile court, which committed a 13-year-old juvenile to
the Youth Rehabilitation and Treatment Center (YRTC) in
Kearney, Nebraska. At issue is whether the court had the
authority under Neb. Rev. Stat. § 43-286(1)(b)(i) (Supp. 2013)
to so commit the juvenile when he was under the age of 14
years. The Office of Juvenile Services (OJS) initially refused
to accept the juvenile, but was ordered by the court to do so.
OJS then accepted him but quickly discharged him, causing
the appeals before us to become moot. The Department asks
us to decide the statutory issue presented under the public
    Nebraska Advance Sheets
432	289 NEBRASKA REPORTS



interest exception to the doctrine of mootness. For the reasons
discussed, we decline to do so and dismiss the appeals.

                         BACKGROUND
   Nathaniel M., born in May 2000, is the subject of three
juvenile proceedings in the county court for Madison County.
The first, which is our case No. S-13-1066, originated on June
29, 2012, with the filing of a petition alleging that Nathaniel
was a juvenile as defined by Neb. Rev. Stat. § 43-247(1) and
(3)(b) (Reissue 2008), based in part on allegations of assault
and criminal mischief. Nathaniel admitted the allegations in
the petition, and at an August 30 disposition hearing, he
was committed to OJS for placement at the foster or group
home level.
   Case No. S-13-1067 originated on May 8, 2013, when a
petition was filed in York County, Nebraska, alleging that
Nathaniel stole property worth more than $1,500 and operated
another’s vehicle without consent. Nathaniel admitted to the
theft, and the other allegation was dismissed. The case was
then transferred to Madison County. On July 29, Nathaniel was
committed to OJS.
   Case No. S-13-1068 originated on September 19, 2013,
when a petition was filed in Madison County alleging
Nathaniel exercised control over the movable property of
another worth $500 or more with the intent to deprive them
thereof. The petition was later amended to add allegations of
theft by receiving stolen property and criminal mischief. A day
after this petition was filed, the State moved for a higher level
of placement for Nathaniel with respect to the two prior pend-
ing juvenile cases.
   A hearing on all three cases was held on November 12, 2013.
In the first two cases, the hearing addressed the State’s motion
for a higher level of placement. In the third case, the hearing
was a pretrial hearing. At this hearing, Nathaniel admitted to
certain allegations in the third case. A caseworker employed
by the Department testified that Nathaniel was a flight risk,
that he posed a risk to himself and others, that no disposition
less restrictive than commitment to the YRTC would suffice to
meet his needs, and that such commitment was in Nathaniel’s
                   Nebraska Advance Sheets
	                IN RE INTEREST OF NATHANIEL M.	433
	                        Cite as 289 Neb. 430

best interests. The parties stipulated that he should be placed at
the YRTC in Kearney in all three cases.
   The court placed Nathaniel on intensive supervised proba-
tion and ordered that he be placed at the YRTC. The court
explained its disposition to Nathaniel as follows:
      Basically it means even though I’ve told you you’re on
      probation until you’re 19, what’s going to happen is . . .
      that you’re going to go to Kearney, and you’re going to
      be expected to complete the program there. And they will
      keep you there until you do complete that program.
At the time of this disposition, Nathaniel was less than 14
years old.
   Two days later, the prosecutor filed a motion for change of
disposition in each of the three cases. At a hearing on these
motions, at which representatives of the Department were pres-
ent, the prosecutor advised the court that the YRTC refused
to accept Nathaniel because of his age and asked the court to
rescind its prior order placing him at the YRTC in accordance
with a stipulation entered into by the parties.
   The court refused to change its disposition. It explained that
it construed § 43-286(1)(b)(i) to authorize the commitment
of a juvenile under the age of 14 to a YRTC if the juvenile
was committed to OJS prior to July 1, 2013; the juvenile had
subsequently committed another offense; and the interests of
the juvenile and the welfare of the community demanded such
commitment. The court found that Nathaniel met these criteria.
And the court further explained:
         And I’m just not going to stand for the fact that the
      [D]epartment [and OJS are] able to say, we don’t agree
      with you, and without appealing they refuse to take the
      child under my order.
         When the court has entered an order . . . the court
      expects that order to be followed unless there is an appeal
      or something else happens. And so if the [D]­epartment
      wants to appeal that, [it] certainly can appeal it. And, in
      fact, if the juvenile is not taken back into the [YRTC],
      I’m ordering that the director . . . at the [YRTC] at
      Kearney, that that person appear here in the court on
      November the 19th at ten o’clock to show cause why
    Nebraska Advance Sheets
434	289 NEBRASKA REPORTS



     they should not be held in contempt of court for refusing
     to follow my order.
         I mean . . . if I ordered anybody else to do something
     and they refused to do it, I wouldn’t just let them say, I
     disagree with your interpretation of the law and so I’m
     not going to do it. And I don’t think that the [YRTC]
     at Kearney or the [D]epartment should be able to do
     that either.
         There are proper procedures for challenging a court’s
     order, and just saying we’re not going to do it and we’re
     not going to take the kid is not one of them. . . . I’ve
     ordered them to take him back.
         If they don’t do it, then they’re ordered to be here on
     the 19th and explain why they’re not taking him back.
     And if they want to, the 30 days has not yet run, they can
     appeal, but that’s the proper way to do it, not just to say
     we’re going to refuse to do what you’ve told us to do.
         I mean, how would that be any different than if I
     ordered the [D]epartment to pay for something and [it
     says], well, [it] interpret[s] the law differently than you
     do, [it is] not going to do it? I mean, there’s plenty of
     cases out there where the [D]epartment has disagreed
     with the court, and [it has] appealed, and sometimes the
     Supreme Court finds for the [D]epartment. That’s the
     proper way to do it, not just to refuse to do it.
         ....
         The [D]epartment just basically says that [it]
     disagree[s] with the way you read the law and so [it is]
     just not going to follow it. And I don’t care if it’s [the
     Department’s] attorney or whoever. I mean, attorneys
     can disagree with me on my interpretation of the law, but
     it’s my job to interpret the law. And if they disagree with
     me, there are ways that they can go about doing that,
     not just say, we’re not going to follow what you said. I
     mean, if that is allowed, what power does the court have
     at that point?
  The records do not reflect whether the referenced contempt
proceedings were held, although counsel for the Department
mentioned such proceedings during oral argument before this
                       Nebraska Advance Sheets
	                    IN RE INTEREST OF NATHANIEL M.	435
	                            Cite as 289 Neb. 430

court. The Department filed notices of appeal in each case on
December 9, 2013.
   Nathaniel was ultimately accepted by the YRTC. The record
indicates, however, that the court was almost immediately
advised by the YRTC that Nathaniel would be discharged in
60 days.1 At a reentry hearing held on January 9, 2014, the
court left Nathaniel’s probation in effect and placed him at a
group home upon his discharge from the YRTC. The parties
agree that Nathaniel was discharged from the YRTC after these
appeals were filed.
   We moved these cases to our docket on our own motion
pursuant to our statutory authority to regulate the caseloads of
the appellate courts of this state.2
                ASSIGNMENTS OF ERROR
   The Department assigns that the juvenile court erred in (1)
placing Nathaniel at a YRTC when he was less than 14 years
old and (2) overruling its motions to change that disposition.
                  STANDARD OF REVIEW
   [1,2] Because mootness is a justiciability doctrine that oper-
ates to prevent courts from exercising jurisdiction, an appel-
late court reviews mootness determinations under the same
standard of review as other jurisdictional questions. When a
jurisdictional question does not involve a factual dispute, its
determination is a matter of law, which requires an appellate
court to reach a conclusion independent of the decisions made
by the lower courts.3
   [3] Statutory interpretation is a question of law that an
appellate court resolves independently of the trial court.4
                        ANALYSIS
  The Department contends that the juvenile court lacked
authority to commit Nathaniel to the YRTC, because Neb. Rev.

 1	
      See, generally, § 43-286(1)(b)(ii).
 2	
      Neb. Rev. Stat. § 24-1106(3) (Reissue 2008).
 3	
      In re Interest of Anaya, 276 Neb. 825, 758 N.W.2d 10 (2008).
 4	
      DMK Biodiesel v. McCoy, 285 Neb. 974, 830 N.W.2d 490 (2013); Mutual
      of Omaha Bank v. Murante, 285 Neb. 747, 829 N.W.2d 676 (2013).
    Nebraska Advance Sheets
436	289 NEBRASKA REPORTS



Stat. § 43-251.01(4) (Supp. 2013) provides: “A juvenile under
the age of fourteen years shall not be placed with or committed
to a youth rehabilitation and treatment center[.]” But the juve-
nile court found that this general prohibition was subordinated
to the specific provisions of § 43-286(1)(b)(i), which apply
to “all juveniles committed to [OJS] prior to July 1, 2013.”
Section 43-286(1)(b)(i) prohibits placement of a juvenile under
the age of 14 years at a YRTC “unless he or she has violated
the terms of probation or has committed an additional offense
and the court finds that the interests of the juvenile and the
welfare of the community demand his or her commitment.”
The juvenile court reasoned that Nathaniel was originally
committed to OJS in the first of these three juvenile cases
on August 30, 2012, that he subsequently committed another
offense, and that his best interests and the welfare of the com-
munity demanded his confinement.
   Both §§ 43-251.01(4) and 43-286(1)(b)(i) are part of the
Nebraska Juvenile Code, which was substantially amended
by the Nebraska Legislature in 2013.5 As we noted in In re
Interest of Marcella G.,6 L.B. 561 authorized a pilot project
administered by the Office of Probation Administration to be
expanded statewide in a three-step, phase-in process begin-
ning July 1, 2013. As a result of this legislation, the Office of
Probation Administration has taken over the previous duties of
OJS with respect to community supervision and parole of juve-
nile law violators and evaluations of such juveniles, while the
role of OJS is now limited to operating YRTC’s and taking care
and custody of juveniles placed at those facilities.7
   [4,5] These cases became moot by OJS’ decision to dis-
charge Nathaniel from the YRTC shortly after his arrival
there. A moot case is one which seeks to determine a question
which does not rest upon existing facts or rights, in which the
issues presented are no longer alive.8 The central question in

 5	
      See 2013 Neb. Laws, L.B. 561.
 6	
      In re Interest of Marcella G., 287 Neb. 566, 847 N.W.2d 276 (2014).
 7	
      See id.
 8	
      Professional Firefighters Assn. v. City of Omaha, 282 Neb. 200, 803
      N.W.2d 17 (2011).
                        Nebraska Advance Sheets
	                     IN RE INTEREST OF NATHANIEL M.	437
	                             Cite as 289 Neb. 430

a mootness analysis is whether changes in circumstances that
prevailed at the beginning of litigation have forestalled any
occasion for meaningful relief.9 Nathanial’s discharge from the
YRTC is clearly such a change in circumstances.
   [6] Acknowledging that the cases are moot, the Department
asks us to decide them under the public interest exception
to the mootness doctrine. An appellate court may choose to
review an otherwise moot case under the public interest excep-
tion if it involves a matter affecting the public interest or when
other rights or liabilities may be affected by its determina-
tion.10 This exception requires a consideration of the public or
private nature of the question presented, the desirability of an
authoritative adjudication for future guidance of public offi-
cials, and the likelihood of future recurrence of the same or a
similar problem.11
   We focus here on the third element of the test. Like Neb.
Rev. Stat. § 43-247.02(3) (Supp. 2013), which we examined
in In re Interest of Marcella G., § 43-286(1)(b)(i) is part of
the process of phasing in the provisions of L.B. 561. It applies
only to juveniles committed to OJS prior to July 1, 2013. With
the passage of time, there will necessarily be fewer juveniles
committed to OJS prior to July 1, 2013, who are under the age
of 14 years and potentially subject to commitment to a YRTC
pursuant to § 43-286(1)(b)(i). At some point, perhaps in the
not-too-distant future, there will be none. During oral argu-
ment, the Department acknowledged that its records would
reflect the date of birth and date of commitment of each
juvenile currently committed to OJS and that based on such
records, it should know precisely how many juveniles could
be affected by the interpretation of § 43-286(1)(b)(i), which
it challenges in these cases. But it has not provided this court
with that information. Instead, in its response to our show

 9	
      Blakely v. Lancaster County, 284 Neb. 659, 825 N.W.2d 149 (2012); In re
      2007 Appropriations of Niobrara River Waters, 278 Neb. 137, 768 N.W.2d
      420 (2009).
10	
      In re Interest of Taylor W., 276 Neb. 679, 757 N.W.2d 1 (2008); In re
      Applications of Koch, 274 Neb. 96, 736 N.W.2d 716 (2007).
11	
      Id.
    Nebraska Advance Sheets
438	289 NEBRASKA REPORTS



cause order, the Department states only that there are “several
other juveniles who were committed to [OJS] prior to July 1,
2013, who are under the age of 14 years.” Thus, we can only
speculate regarding the probability of a future recurrence of the
issue presented in these appeals. It appears, however, that such
probability is slight.
   And in the increasingly unlikely event that the issue did
recur, it would not necessarily escape appellate review, as
the Department contends. These cases are moot because OJS
made them so by discharging Nathaniel from the YRTC
shortly after he arrived there. OJS is a statutorily created
office within the Department to which a court may commit
a juvenile for treatment, including supervision, care, con-
finement, and rehabilitative services.12 The record suggests,
and counsel for the Department confirmed at oral argument,
that OJS discharged Nathaniel from the YRTC not because
he completed a treatment program there, but at least in part
because OJS and the Department disagreed with the juvenile
court’s interpretation of the law regarding its authority to
commit Nathaniel to the YRTC—the precise issue which the
Department asks us to decide in these appeals. Remarkably, in
urging us to reach the merits of these appeals, the Department
states in its brief:
      As the law stands now, should a judge enter an order
      committing one of these juveniles under the age of four-
      teen to a YRTC, the YRTC will act, as it did in these
      cases, and discharge the juvenile almost immediately
      because the statutes do not allow for such a commit-
      ment. At the current time, the only way the YRTC can
      comply with the law while following a court order com-
      mitting a juvenile under the age of fourteen is to accept
      the juvenile into the YRTC and then discharge the juve-
      nile promptly.13
   That is not how the law stands now. It is apparent that the
stern but appropriate admonition of the juvenile court which

12	
      Neb. Rev. Stat. §§ 43-403(2) and (7) (Reissue 2008) and 43-404(1) (Supp.
      2013).
13	
      Brief for appellant at 20.
                        Nebraska Advance Sheets
	                              HUSKEY v. HUSKEY	439
	                              Cite as 289 Neb. 439

we have quoted above has not disabused the Department of
the notion that it is free to disregard a court order with which
it disagrees. So we add our own admonition: In the seemingly
unlikely event that the circumstances presented here should
arise in the future, the Department, OJS, and the YRTC can,
and indeed must, comply with the juvenile court’s order, and
it is their statutory duty to provide appropriate treatment to a
juvenile committed to their care and custody unless and until
an appellate court reverses or modifies the commitment order.
Statutory interpretation and construction is a function of the
judicial branch, not the executive branch.
   Based upon the manner in which these cases became moot,
and the distinct possibility that the issue presented is one
of last impression, we decline to reach the merits of these
appeals under the public interest exception to the doctrine
of mootness.
                        CONCLUSION
   For the foregoing reasons, we lack appellate jurisdiction over
these appeals because the issue presented is moot. Accordingly,
the appeals are dismissed.
                                            Appeals dismissed.
   Heavican, C.J., not participating.


    Curtis Charles Huskey, appellant and cross-appellee, v.
      Deitra Marie Huskey, now known as Deitra Marie
           Osterfoss, appellee and cross-appellant.
                                  ___ N.W.2d ___

                     Filed November 7, 2014.     No. S-13-1140.

 1.	 Statutes: Appeal and Error. Statutory interpretation presents a question
     of law, which an appellate court reviews independently of the lower court’s
     determination.
 2.	 Jurisdiction: Appeal and Error. It is the duty of an appellate court to determine
     whether it has jurisdiction over the matter before it.
 3.	 Constitutional Law: Jurisdiction: Appeal and Error. Except in those cases
     wherein original jurisdiction is specially conferred by Neb. Const. art. V, § 2,
     the Nebraska Supreme Court exercises appellate jurisdiction, and such appellate
     jurisdiction can be conferred only in the manner provided by statute.
 4.	 Appeal and Error. The right of appeal in Nebraska is purely statutory.
