
550 P.2d 1403 (1976)
STATE of Oregon, Appellant,
v.
Robert Samuel REAVES, Respondent.
Court of Appeals of Oregon.
Argued and Submitted April 21, 1976.
Decided June 21, 1976.
Catherine Allan, Asst. Atty. Gen., Salem, argued the cause for appellant. With her on the brief were Lee Johnson, Atty. Gen. and W. Michael Gillette, Sol. Gen., Salem.
Imants Osis, Portland, argued the cause and filed the brief for respondent.
Before SCHWAB, C.J., and FORT and LEE, JJ.
SCHWAB, Chief Judge.
This is an appeal by the state from an order suppressing breathalyzer test results on the ground that the state did not make available the breathalyzer test ampule for defendant's independent testing.
This issue is controlled by our recent decision in State v. Michener, 25 Or. App. 449, 550 P.2d 449 (1976). In that case, we rejected the California rule[1] that requires that breathalyzer ampules always be made available for independent testing. Instead, following the Oregon authorities,[2] we concluded that a defendant must establish
"* * * some reasonable possibility, based on concrete evidence rather than a fertile imagination, that * * * [the breathalyzer ampule] would be favorable to his cause." 25 Or. App. at ___, 550 P.2d at 454.
In Michener the required showing of potential favorableness consisted of video tapes *1404 of the defendants at the time of their arrests that raised a serious question about the accuracy of the breathalyzer test results.
In this case, there is no evidence that retesting of the breathalyzer ampule might produce evidence favorable to the defendant. On such a record, a motion to suppress breathalyzer test results must be denied. State v. Michener, supra.
However, we conclude defendant's attempt to make a record on this issue was prematurely cut off by the erroneous ruling of the trial court:
"[DEFENSE COUNSEL]: May I put on one [additional] witness?
"THE COURT: What's he going to testify to?
"[DEFENSE COUNSEL]: As to the condition of [defendant] at the * * * time of his arrest.
"* * *
"THE COURT: I've got enough to rule on this point. You are saying `his condition.' You mean as to sobriety?
"[DEFENSE COUNSEL]: Yes.
"THE COURT: No, I don't want to hear it. That's got nothing to do with it. * * *"
On this record, we think it appropriate to allow defendant, on remand, to renew his motion to suppress and attempt to sustain his burden under Michener.
This is not to suggest that testimony of one or more witnesses to the effect that a driver appeared sober at the time of his arrest would necessarily constitute a sufficient showing of favorableness under Michener. The trial court, as factfinder, must first pass on the credibility of the witnesses, just as is true when other questions arise at pretrial evidentiary hearings, such as whether warnings preceded a confession or there was consent to conduct a search. In other words, the "fertile imagination" we referred to in Michener can include sworn testimony at a suppression hearing.
And even credible testimony that the defendant appeared sober at the time of his arrest would not necessarily constitute a sufficient showing of favorableness under Michener. As we noted in Boyd v. Francis Ford, Inc., 12 Or. App. 26, 504 P.2d 1387 (1973), a case where there was testimony that a person with a .37 percent blood alcohol level "appeared sober,"
"* * * a person who could achieve such a [blood alcohol] level would have had considerable experience with alcohol, would have been drinking for quite a few hours before achieving it, and might not outwardly show the effects of the alcohol." 12 Or. App. at 28, 504 P.2d at 1389.
We also said the experienced drinker "* * * could deceive the casual observer as to his inebriated condition." 12 Or. App. at 31, 504 P.2d at 1390.
Reversed and remanded.
NOTES
[1]  People v. Hitch, 12 Cal.3d 641, 117 Cal. Rptr. 9, 527 P.2d 361 (1974).
[2]  State v. Koennecke, 274 Or. 169, 545 P.2d 127 (1976); State ex rel. Dooley v. Connall, 257 Or. 94, 475 P.2d 582 (1970); State v. Hockings, Or. App., 75 Adv.Sh. 3802, 542 P.2d 133 (1975), Sup.Ct. review denied (1976); State v. Jones, 18 Or. App. 343, 525 P.2d 194, Sup.Ct. review denied (1974); State v. Williams, 11 Or. App. 255, 500 P.2d 722 (1972); Hanson v. Cupp, 5 Or. App. 312, 484 P.2d 847 (1971).
