Defendant assigns as error the overruling of his motion to dismiss the action for the reason that he was denied a speedy trial as guaranteed by the Sixth Amendment to the Federal Constitution.
In State v. Johnson, 275 N.C. 264, 269, 167 S.E. 2d 274 (1969), opinion by Justice Sharp, we find:
“Decisions of this Court establish:
“1. The fundamental law of the State secures to every person formally accused of crime the right to a speedy and impartial trial, as does the Sixth Amendment to the Federal Constitution (made applicable to the State by the Fourteenth Amendment, Klopfer v. North Carolina, 386 U.S. 213, 18 L.Ed. 1, 87 S.Ct. 988 (1967).
“2 * * *
“3. Undue delay cannot be categorically defined in terms of days, months, or even years; the circumstances of each particular case determine whether a speedy trial has been afforded. Four interrelated factors bear upon the question: the length of the delay, the cause of the delay, waiver by the defendant, and prejudice to the defendant.
“4. The guarantee of a speedy trial is designed to protect a defendant from the dangers inherent in a prosecution which has been negligently or arbitrarily delayed by the State; prolonged imprisonment, anxiety and public distrust engendered by untried accusations of crime, lost evidence and witnesses, and impaired memories.
“5. The burden is on an accused who asserts the denial of his right to a speedy trial to show that the delay was due to the neglect or willfulness of the prosecution. A defendant who has himself caused the delay, or acquiesced in it, will not be allowed to convert the guarantee, designed for his protection, into a vehicle in which to escape justice. (Citations.) ”
*735In State v. Brown, 282 N.C. 117, 123, 191 S.E. 2d 659 (1972), opinion by Justice Moore, we find: “The word ‘speedy’ cannot be defined in specific terms of days, months or years, so the question whether a defendant has been denied a speedy trial must be answered in light of the facts in the particular case. The length of the delay, the cause of the delay, prejudice to the defendant, and waiver by defendant are interrelated factors to be considered in determining whether a trial has been unduly delayed. (Citations.)”
In the instant case, defendant failed to show that the delay in his trial was due to the neglect or willfulness of the prosecution. To the contrary, the record discloses that subsequent to 19 October 1969 Tpr. Smith was transferred from Randolph County and thereafter separated from the State Highway Patrol and became a U. S. Deputy Marshal; that he was serving as a deputy marshal, stationed in Raleigh, at the time of the trial. The record further indicates that defendant was free on a nominal bond most, if not all, of the time between the date of the alleged offense and the date of his trial. There is no showing that defendant was prejudiced by the delay in any way. The assignment of error is overruled.
Defendant assigns as error the admission of testimony showing the result of the breathalyzer test administered to him in the hospital. In connection with this assignment, defendant argues that the court should not have admitted any evidence tending to show that he was operating a motor vehicle upon a public highway while under the influence of intoxicants. We reject this argument. Evidence of defendant’s operating a motor vehicle while under the influence of intoxicants was relevant to show that Tpr. Smith had probable cause to arrest defendant and that defendant was in the lawful custody of Tpr. Smith at the time of the alleged assault.
As to the admission of testimony showing the result of the breathalyzer test, G.S. 20-139.1 (a) provides in pertinent part as follows: “In any criminal action arising out of acts alleged to have been committed by any person while driving or operating a vehicle while under the influence of intoxicating liquor, the amount of alcohol in the person’s blood at the time alleged as shown by chemical analysis of the person’s breath or blood shall be admissible in evidence. . . .”
*736Since defendant in the case at bar was not driving or operating a vehicle at the time of the alleged assault on Tpr. Smith, we hold that the court erred in admitting testimony showing the result of the breathalyzer test; however, we do not think the error was prejudicial to defendant. State v. Wade, 14 N.C. App. 414, 188 S.E. 2d 714 (1972); cert. den., 281 N.C. 627, 190 S.E. 2d 470 (1972). Without the evidence disclosing the result of the breathalyzer test, there was plenary evidence tending to show defendant’s intoxication at the time he was operating a vehicle, thereby establishing probable cause for his arrest. The jury was not passing upon the question of defendant’s guilt of operating a vehicle while under the influence of intoxicants; its inquiry was whether Tpr. Smith had probable cause to believe that defendant was guilty of operating a vehicle while under the influence of intoxicants. The assignment of error is overruled.
We have carefully considered the other assignments of error brought forward and argued in defendant’s brief but finding them without merit, they too are overruled.
No error.
Judges Britt and Vaughn concur.