On Petition for Rehearing
MARING, Justice,on petition for rehearing.
[¶ 31] Syvertson has filed a petition for rehearing, contending he was denied oral arguments despite his request. Although we deny his petition, we take this opportunity to clarify our decision.
[¶ 32] On January 20, 2000, Syvertson filed a “NOTICE OF MOTIONS FOR HEARING.” He stated:
Oral arguments and [e]videntiary [h]ear-ing will be held ... at a time and date that Syvertson will set and notify the respondents of after responses, repl[i]es, orders accordingly, ap[p]rop[r]iate amendments and motions and orders related, review of transcripts and tapes[ ]by Syvertson and any experts, *370applications for [s]ubp[oe]nas filed and issued for needed witnesses.
[¶ 33] The State served and filed on February 22, 2000, a “Response by Answer Or Motion Of State Of North Dakota To Petitioner’s Post Conviction Application dated January 16, 2000 And Filed on January 20, 2000.” Therein, the State requested the court grant its motion for dismissal or summary disposition under § 29-32.1-09, N.D.C.C.
[¶ 34] Subsequently, on March 2, 2000, Syvertson filed a “NOTICE OF MOTIONS FOR HEARING,” stating:
Take notice that the petitioner in the above titled action brings on for hearing [t]he State[’]s Answer or motion of State of ND for dismissal or summary [disposition] and Syvertson’s cross[-]motion for [s]ummary disposition, at the [C]ass county court house, box 2806, Fargo, ND, at a time and date set by the calender clerk and which will be no-tif[i]ed in the fut[u]re....
Syvertson contends he also sent a letter, dated February 29, 2000, to the calender clerk. This letter reads:
Please set a hearing for the [S]tate[’]s .motion for summary [disposition] and Syvertson[’s] cross[-]motion for summary [disposition] in the above titled matter. This hearing will need to be set for a time in the future not to conflict with responses and other matters relevant. I am in the ND State Pen and will need [to be] transported for such a hearing thus a transport order will need [to be] prepa[ ]red.
[¶ 35] On March 24, 2000, the trial court filed a memorandum opinion summarily dismissing the application for post-conviction relief. A judgment of dismissal was filed April 7, 2000.
[¶ 36] In his petition for rehearing, Syvertson argues our Court overlooked his letter to the calender clerk. Under Rule 3.2, N.D.R.Ct., Syvertson contends he is entitled to oral argument because he requested the clerk provide him with a date. The letter, dated February 29, 2000, asking the calender clerk to set a hearing for the State’s motion for summary disposition and Syvertson’s cross-motion for summary disposition, however, is not in the certified record of this appeal. The letter is only found in Syvertson’s appendix on appeal. “Only items actually in the record may be included in the appendix.” N.D.RApp.P. 30(a). Syvertson never made a motion to supplement the record under Rule 10(h), N.D.R.App.P. Our Court has stated many times we will not consider documents not in the certified record. State v. McKinney, 518 N.W.2d 696, 703 (N.D.1994). However, our Court has the authority to supplement the record on its own motion with a document that was before the trial court. N.D.R.App.P. 10(h). It appears from an affidavit of service this letter was served on the clerk of the court and on the State’s Attorney.
[¶ 37] Assuming, without deciding, Syvertson’s request complies with Rule 3.2, we nevertheless conclude that even if the trial court erred in denying Syvertson oral arguments, it was harmless error. N .D.R.Crim.P. 52(a); N.D.R.Civ.P. 61. “Any error, defect, irregularity or variance which does not affect substantial rights shall be disregarded.” N.D.R.Crim.P. 52(a). This Court’s objective in reviewing nonconstitutional error is to determine whether the error was so prejudicial that substantial injury occurred and a different decision would have resulted without the error. State v. Steen, 2000 ND 152, ¶ 13, 615 N.W.2d 555.
[¶ 38] The trial court’s failure to grant Syvertson oral argument was a procedural oversight and not prejudicial. Sy-vertson moved the court for summary disposition with accompanying briefs and conceded that no facts were in dispute. Syvertson’s application for post-conviction relief was denied on the grounds his *371claims have been fully and finally decided in a previous proceeding, misuse of process, and failure to raise a genuine issue of material fact of prejudice. We, therefore, conclude there is nothing in this record to indicate the trial court would have arrived at a different result had it granted Syvert-son oral argument.
[¶ 39] VANDE WALLE, C.J., NEUMANN, SANDSTROM, KAPSNER, JJ., concur.