Defendant appeals his convictions for theft in the first degree, ORS 164.055, unauthorized use of a motor vehicle, ORS 164.135, and conspiracy. ORS 161.450. We reverse and remand.
Defendant was employed for 20 years as a truck driver for United Grocers. About 3:30 a.m. on December 18, 1985, he was having breakfast, as he customarily did, at a restaurant in Sherwood. He had parked his truck in the restaurant lot and had left the keys in it. He went into the restaurant and sat at the counter next to Spindler, with whom he talked. Defendant knew Spindler and knew that he had a criminal record.1 While the two were talking, Bradbrook drove the truck from the lot. Spindler then left. Another truck driver entered the restaurant and told defendant that his truck was no longer parked outside. Defendant finished his coffee, left the restaurant and, about 20 minutes later, returned and reported the theft to a deputy sheriff who had been in the restaurant before defendant had gone outside. Acting on a tip, the police recovered the truck and some of the groceries the following day. The charges against defendant arose out of the incident. For their participation in the heist, Spindler, Bradbrook and Billy Minor were convicted of theft before defendant’s trial.
Defendant first assigns error to the trial court’s denial of his motion to dismiss for lack of a speedy trial.2 Defendant was indicted on March 21, 1986, and trial was scheduled for June 17. On the day of trial, the state moved for a continuance because Spindler, whom the state was going to call as a witness, had changed his original story that defendant was involved in the theft. The prosecutor was concerned that he might have to be an impeachment witness and thought that a special prosecutor might have to be appointed. The trial court granted a continuance over defendant’s objection, and trial was reset to and held on October 8. Defendant argues that the delay at the state’s request was prejudicial because, during the four-month delay, a material witness, Joy Jonas, died.
*333 Under the Oregon Constitution, a court must consider the length of the delay, the reason for the delay and any prejudice to the defendant in determining whether there has been a denial of a speedy trial. State v. Ivory, 278 Or 499, 564 P2d 1039 (1977).3 The four-month delay here is not presumptively prejudicial, and its cause was not within the state’s control. See State v. Taylor, 57 Or App 553, 645 P2d 547 (1982). Furthermore, the prosecutor stipulated that Jonas, who had been involved in the theft, would have testified that she was not aware that defendant was involved in a conspiracy or the theft. Her testimony was superfluous in the light of the stipulation. See n 5, infra. Defendant has not shown how the failure to have that testimony prejudiced his defense. The trial court did not abuse its discretion in denying the motion.4
At trial, Spindler, Bradbrook and Minor all testified that defendant did not participate in the crime.5 Defendant assigns error to the trial court’s giving this instruction:
“You are instructed that as a matter of law Christopher Spindler, William Bradbrook, and Billy Minor are accomplice witnesses in this case in the commission of the crimes of theft in the first degree, unauthorized use of a vehicle and conspiracy.
“The other evidence that is required to corroborate the testimony of a witness may not be supplied by the testimony of another accomplice or accomplices. It must instead come from other evidence apart from the activity of another accomplice or accomplices.
“When you find that a person is an accomplice witness, then you should view that accomplice witness’ testimony with distrust.”
Accomplice testimony is governed by ORS 136.440:
*334“(1) A conviction cannot be had upon the testimony of an accomplice unless it is corroborated by other evidence that tends to connect the defendant with the commission of the offense. The corroboration is not sufficient if it merely shows the commission of the offense or the circumstances of the commission.
“(2) As used in this section, an ‘accomplice’ means a witness in a criminal action who, according to the evidence adduced in the action, is criminally liable for the conduct of the defendant under ORS 161.155 and 161.165 * * (Emphasis supplied.)
ORS 161.155 provides, in part:
“A person is criminally liable for the conduct of another person constituting a crime if:
«* * * Hc *
“ (2) With the intent to promote or facilitate the commission of the crime the person:
“(a) Solicits or commands such other person to commit the crime; or
“(b) Aids or abets or agrees or attempts to aid or abet such other person in planning or committing the crime * *
Defendant argues that an accomplice witness instruction should never be given when the accomplice testimony tends to exonerate a defendant, as it did here. We rejected that argument in State v. Lewis, 10 Or App 154, 499 P2d 343 (1972), where the accomplice witness’ testimony did not implicate the defendant, and we held that the trial court did not err by instructing that the testimony should be viewed with distrust. Defendant argues, however, that Lewis was wrongly decided, because it was decided in July, 1972, and the commentary to what is now ORS 136.4406 was published in November, 1972. Defendant contends that the commentary shows that the purpose of the instruction is to prevent an accomplice from trying to gain the conviction of an innocent person through perjured testimony in exchange for immunity. Commentary, Proposed Oregon Criminal Procedure Code 204 (1972).
A statutory provision for corroboration of accomplice *335testimony has existed in substantially the same form since 1864. See State v. Winslow, 3 Or App 140, 145, 472 P2d 852 (1970). Before Lewis, both the Supreme Court and we had noted the rationale for the rule on which defendant relies. See State v. Nice, 240 Or 343, 401 P2d 296 (1965); State v. Smith, 1 Or App 583, 465 P2d 247 (1970). In Lewis, we rejected the proposition that the only rationale for viewing the testimony of an accomplice with caution arises from the possible motivation for the testimony. We found, rather, that another basis for mistrusting the testimony is that the witness was a participant in the crime at issue.
Although an accomplice witness instruction is usually given when the witness’s testimony is to the effect that the defendant committed the crime charged, there is no generalized reason why the instruction should never be given if there is evidence from which a jury could infer that a witness is tied to a defendant in the commission of a crime in the manner defined by ORS 161.155. Still, we agree with defendant that, in the circumstances of this case, the instruction was wrong in that it instructed that the witnesses were accomplices as a matter of law.
The test for determining if a witness is an accomplice is whether the witness could be indicted as an accomplice to the offense charged against the defendant. State v. Hull, 286 Or 511, 516, 595 P2d 1240 (1979). The state contends that, given that the witnesses had not only been indicted but convicted for theft of the truck, they were accomplices as a matter of law. That argument erroneously makes the issue the crimes committed by the witnesses, not, as required by the express words of the statute, whether the witnesses were criminally liable for a crime committed by defendant. Proof of the witnesses’ convictions for their own acts does not, by itself, show that they were accomplices of defendant in his alleged crimes.
That the witnesses could be — and in fact were — charged with a crime in which defendant is alleged to have participated is not in dispute. What is in dispute is the link to defendant. The witnesses denied that they were involved with him, and he also denied it. Thus, there was a factual issue for the jury’s determination as to whether the other evidence showed that, despite their denial, the witnesses were in fact involved with defendant in a crime. If the jury *336were so to find, the testimony of the witnesses could be viewed with distrust.
To instruct that the witnesses were accomplices as a matter of law was not harmless error. The instruction said, in effect, that they had in fact participated in criminal acts with defendant. There was no undisputed evidence that they had participated with defendant in anything. That was a determination for the jury to make.7
Reversed and remanded for a new trial.
Defendant at first denied to police that he knew Spindler. He later admitted that he did.
Or Const, Art I, § 10; US Const, Amend VI.
The federal test also encompasses whether the accused asserted the right to a speedy trial. Barker v. Wingo, 407 US 514, 92 S Ct 2182, 33 L Ed 2d 101 (1972). There is no question but that defendant asserted his right.
The court also did not err in denying defendant’s motion for judgment of acquittal. There was sufficient circumstantial evidence for the jury to consider.
Spindler testified that defendant had no knowledge that the crime was going to happen and was not a participant at all. Bradbrook testified that, when he took the truck away, he did not know defendant’s name, did not have any knowledge of defendant’s involvement and was concerned that defendant might see him driving off in his truck without his permission. Minor testified that his only involvement was that Bradbrook hired him to unload the truck after it was stolen.
ORS 136.440 is former ORS 136.550.
Because of the reasons for our disposition of the appeal, we do not reach defendant’s assignment of error that the court erred in failing to merge the convictions for theft and conspiracy, which the state concedes.