[¶ 1] Bruce Roger Mills, individually and on behalf of those similarly situated, appeals from a judgment dismissing his claims against the City of Grand Forks to recover the amount of fines and fees collected in the past for noncriminal traffic violations by the City exceeding the amount the City could legally impose under state law. The City cross-appeals from the judgment. Because the district court correctly ruled Mills’s claims are barred by res judicata, we affirm the judgment.
I
[¶ 2] On July 7, 2004, a Grand Forks police officer cited Mills with careless driving, a noncriminal offense proscribed by Grand Forks City Code § 8-0701. Under Grand Forks City Code § 8-1502, the maximum fine for violation of a noncriminal offense was $1,000 “in the discretion of the court.” Mills pled not guilty and proceeded to trial in municipal court. Mills was found guilty. On August 19, 2004, the municipal court imposed against Mills “a fine in the amount of $151 with $0 suspended” and a hearing fee of $15. Mills appealed to district court for trial anew, and on September 14, 2004, the court' affirmed the conviction and the fine and fees totaling $166. Mills appealed to this Court, but on December 1, 2004, we dismissed the appeal because the district *576 court judgment was “not appealable under N.D.C.C. § 39-06.1-08(5).” Mills did not petition this Court for a supervisory writ under N.D. Const, art. VI, § 2 and N.D.C.C. § 27-02-04.
[¶ 3] In 2008, we held in
Sauby v. City of Fargo,
[¶ 4] On August 16, 2010, Mills brought a “Class Action Complaint for Restitution” in state district court seeking on behalf of himself and others similarly situated the amount of monies paid to Grand Forks exceeding the state law limits for fines for similar state offenses. Mills asserted the excess fines, fees and charges were “involuntary and void.” Before the court could rule on certification of the class, the City moved to dismiss the complaint under N.D.R.Civ.P. 12, or in the alternative, for summary judgment under N.D.R.Civ.P. 56. The City contended Mills’s claims should be dismissed as a matter of law because they are barred by res judicata and collateral estoppel. The City argued Mills’s claims were precluded by both res judicata and collateral estoppel based on the prior federal court action, and by res judicata because Mills failed to challenge the City’s fine scheme in the 2004 state court proceedings.
[¶ 5] The district court granted the City’s motion to dismiss. The court concluded res judicata and collateral estoppel based upon the federal court action did not bar Mills’s claims in this case because “[tjhose actions determined that there was not a federal claim which is a different claim than [the] one asserted here.” However, the court ruled res judicata based on the 2004 state court proceedings barred this lawsuit because Mills “is now raising a claim that could have been raised in prior litigation with the City.”
II
[¶ 6] On appeal, Mills argues the district court erred in determining his claims were barred by res judicata because he did not challenge the City’s fine scheme during his 2004 state court proceedings. In its cross-appeal, the City argues the court erred in determining res judicata and collateral estoppel do not bar this action based on the prior federal court proceedings. The dispositive issue is whether the court erred in concluding res judicata barred this action because Mills failed to raise the issue in the 2004 state court proceedings.
[¶ 7] “If, on a motion to dismiss under N.D.R.Civ.P. 12(b)(vi), matters outside the pleadings are presented to and not excluded by the district court, the motion is treated as a motion for summary judgment under N.D.R.Civ.P. 56.”
Zutz v. Kamrowski,
[¶ 8] In Missouri Breaks, LLC v. Burns, this Court said:
“We explained res judicata in Hager v. City of Devils Lake,2009 ND 180 , ¶ 10,773 N.W.2d 420 (quoting Riverwood Commercial Park, L.L.C. v. Standard Oil Co., Inc.,2007 ND 36 , ¶ 13,729 N.W.2d 101 ):
‘Res judicata, or claim preclusion, prevents relitigation of claims that were raised, or could have been raised, in prior actions between the same parties or their privies. Thus, res judicata means a valid, existing final judgment from a court of competent jurisdiction is conclusive with regard to claims raised, or those that could have been raised and determined, as to [the] parties and their privies in all other actions. Res judi-cata applies even if subsequent claims are based upon a different legal theory.’
“ ‘Under res judicata principles, it is inappropriate to rehash issues which were tried or could have been tried by the court in prior proceedings.’ Laib v. Laib,2010 ND 62 , ¶10,780 N.W.2d 660 (quoting Wetch v. Wetch,539 N.W.2d 309 , 311 (N.D.1995)). Res judi-cata or claim preclusion ‘bars courts from relitigating claims in order to promote finality of judgments, which increases certainty, avoids multiple litigation, wasteful delay and expense, and ultimately conserves judicial resources.’ Lucas v. Porter,2008 ND 160 , ¶ 16,755 N.W.2d 88 .”
[¶ 9] Mills argues the municipal court and the district court in the 2004 proceedings were not courts of “competent jurisdiction” to impose an excessive fine against him because a traffic fine exceeding statutory authority is void, at least with respect to the portion of the fine exceeding the amount permitted under state law, and “[v]oid judgments may be attacked in any proceeding, directly or collaterally.”
Johnson v. Ranum,
[¶ 10] A court is a court of competent jurisdiction to issue a valid order or judgment if the court has “jurisdiction over both the subject matter of the action and the parties.”
Giese v. Giese,
[¶ 11] In 2004, the municipal court and the district court had subject matter jurisdiction over the careless driving proceedings because they had the “power to hear and determine the general subject involved in the action.”
Giese,
at ¶ 6. There is no question those courts also had jurisdiction or “ ‘power’ ” over the parties.
Interest of M.W.,
at ¶ 5 (quoting
Albrecht v. Metro Area Ambulance,
[¶ 12] “[A]n action based on an omitted defense cannot be permitted in guise of a claim for restitution of a former judgment already paid or for damages measured by its execution.” 18 Charles A. Wright, Arthur R. Miller & Edward H. Cooper, Federal Practice and Procedure § 4414, at 326-27 (2d ed. 2002) (footnote omitted); see also 18 James Wm. Moore, Moore’s Federal Practice § 131.10[3][e] (3d ed. 2011) (“A claim, for purposes of claim preclusion, includes not only those matters actually addressed by the prior judgment, but those matters which could have been raised in that action ... including] any defenses which could have been asserted in the prior litigation.”) (footnote omitted). This principle is illustrated by two decisions of the Vermont Supreme Court.
[¶ 13] In
Chittenden Trust Co. v. MacPherson,
“res judicata, long established in our law, and permit a taxpayer who has lost in one suit and failed to appeal the result to bring a new action hoping for a different outcome. The simple fact is that the prejudgment diligence demonstrated by the fiduciaries in [the prior cases involving challenges in direct appeals from probate court] was not exercised in the estates here in question. Perhaps understandable in the routine administration of estates under a statute unchallenged over a relatively long period, it is nevertheless insufficient reason to disturb a final judgment of a court of competent jurisdiction.”
Id. at 359.
[¶ 14]
MacPherson
was followed by the court in
Merrilees v. Treasurer,
“Although there is no record on this point, the parties do not dispute that members of the plaintiff class were subject to criminal or administrative proceedings in which each paid the surcharge without objecting on constitutional grounds. The [constitutional] issue, without doubt, could have been raised in those proceedings. Instead, these litigants were joined together in a class action, a collateral proceeding initiated after their own individual proceedings were completed, which is precisely the type of attack that MacPher-son condemns.”
Merrilees, at 1316. The court rejected the argument that policies favoring class actions should be recognized over those favoring res judicata when individual claims involve small amounts:
“Here, as in MacPherson, the issue is finality, not the obvious utility of aggregating small claims in a class action. By failing to raise the asserted illegality of the surcharge to the court assessing the charge, plaintiffs, by their own inaction, have created the necessity for aggregation. If they prevail, the burden shifts to the state to locate and reimburse persons who failed to complain about the charge when it was directly before the court. Under these circumstances, plaintiffs’ aggregation argument does not outweigh the need for finality.”
Merrilees,
at 1316-17.
See also Esteves v. Ortiz Alvarez,
[¶ 15] Here, Mills did not challenge in municipal court or in district court the City’s authority to assess traffic fines exceeding those permitted under state law. Although Mills claims he asserted the argument in a petition for rehearing submitted to this Court after dismissal of his appeal, we are unable to divine from review of the document that this argument was specifically raised. But even if the argument was raised in the document, this Court will not consider arguments first raised in a petition for rehearing. See
Northern Pac. Ry. Co. v. Warner,
Ill
[¶ 16] We do not address other arguments raised because they are either without merit or unnecessary to the decision. The judgment is affirmed.