specially concurring.
I am of the opinion that the trial judge erred when he permitted the State’s witness, Officer Terwilleger, to testify concerning appellant’s prior conviction for aggravated assault. I will therefore concur in the result only.
The State, in its case-in-chief, called Officer Terwilleger of the Cheyenne Police Department to the witness stand to testify about appellant’s prior conviction, a necessary element of the charged offense.1 This *87witness was the same officer at whom the appellant had fired a shot in 1973. When the prosecutor asked the witness a question concerning the nature of the previous offense, but before the question was answered, defense counsel offered to stipulate to appellant’s prior conviction. This stipulation — which was accepted by the prosecutor and approved by the court — agreed that appellant’s prior conviction was for a crime which is included within the statute, and that he was the one who committed it. Even so, the trial judge permitted the prosecutor to continue to extract detailed testimony from the witness having to do with the prior offense, including the fact that it involved a shotgun being fired at him. Defense counsel persistently objected to the relevance of the testimony in light of the stipulation that had been entered into and approved by the court. The trial judge admitted the testimony on three grounds: (1) for purposes of identification; (2) for the purpose of proving the element of the crime charged; and (3) for the reason that the testimony was relevant to the probable testimony of the arresting officer.
Notwithstanding the stipulation and the grounds upon which the trial judge admitted the evidence, the majority opinion upholds the admission of the officer’s testimony on a theory that no one else had ever thought of, i.e., that it was relevant to a question concerning the reasonableness of the officer’s arrest and seizure of the weapon. While this justification was urged by the State in its brief before this court, my review of the record does not disclose that the reasonableness of the search and seizure was an issue at trial. The record reflects that the only time a search and seizure question came up was in a pretrial motion to suppress filed by appellant’s counsel. This motion was denied by the judge for lack of jurisdiction. The issue was not raised again at trial, and the instructions do not even intimate that the question was submitted to the jury. This explains why the State did not point to a reference in the transcript when the basis for upholding the admission of the testimony was asserted. It is therefore my conclusion that the majority opinion countenances the admission of the testimony through an imagined justification-one that is not reflected in the record.
In my judgment, the prosecution, upon agreeing to the proposed stipulation, was bound by its terms and it was thereafter improper to offer proof concerning appellant’s prior conviction. See: In re Griffin, 114 Cal.Rptr. 74, 39 Cal.App.3d 279, Ct.App. (1974). If the prosecution wanted to show that the defendant had previously fired a shotgun at Officer Terwilleger, the stipulation should not have been entered into. The case law is clear that the State is not required to enter into a stipulation offered to prove an element of the charged offense, and it is entitled to present the facts proving that element. See: People v. Szeto, 171 Cal.Rptr. 652, 29 Cal.3d 20, 623 P.2d 213 (1981); State v. Duran, Utah, 522 P.2d 1374 (1974); People v. McClellan, 80 Cal.Rptr. 31, 457 P.2d 871 (1969). Here the prosecutor chose to accept the stipulation. At that point there was no necessity or any further relevance for the officer’s testimony concerning the prior conviction for aggravated assault. The State had stipulated to an element of the charged offense, and the trial court erred when it permitted allowing any further testimony. The stipulation did not recite that appellant’s prior conviction had resulted because of the firing of a shotgun at a police officer and the fact that the aggravated assault was committed upon a police officer was irrelevant. The statute, § 6-11-115, supra, does not delineate between aggravated assault committed upon ordinary citizens and that committed upon police officers. Since the stipulation covered the necessary facts to prove an element of the crime, the need for further proof ended.
Even though I am of the opinion that error was committed in admitting Officer *88Terwilleger’s testimony into evidence, I cannot conclude that the error prejudiced the defendant in this case. The burden is on the appellant to show that the complained-of error prejudiced him to such a degree that reversal is required. Belondon v. City of Casper, Wyo., 456 P.2d 238, cert. den., 398 U.S. 927, 90 S.Ct. 1815, 26 L.Ed.2d 89 (1969); Drummer v. State, Wyo., 366 P.2d 20 (1961). Here the jury was presented with substantial evidence proving the elements of the charged offense, which, not including the erroneous testimony, was sufficient to convict appellant. There was no question about the fact that appellant was in possession of a firearm. Under the circumstances, I cannot conclude that there was a reasonable possibility, in the absence of the error, that the verdict in the case would have been any different. Nimmo v. State, Wyo., 603 P.2d 386 (1979); Reeder v. State, Wyo., 515 P.2d 969 (1973). I therefore concur in the result reached by the majority.
. As noted by the majority, appellant was convicted of a violation of § 6-11-115, W.S.1977, Cumm.Supp., 1981. According to the requirements of this statute the State was obliged to prove that appellant had been convicted of one or more of the following crimes: murder, voluntary manslaughter, assault to commit mur*87der, aggravated assault, robbery, burglary or sexual assault in the first or second degree, or mayhem. In this case the proof focused on appellant’s previous conviction for aggravated assault.