dissenting:
I respectfully dissent. The Commonwealth’s evidence was insufficient to support the conviction and I would reverse.
The statute Mahaney was charged with violating required the Commonwealth to prove (1) that Mahaney was operating the vehicle, and (2) that while he was operating it, he was under the influence of alcohol to a degree that rendered him incapable of driving safely. One essential element of the Commonwealth’s case was not proven: that, at the time he was operating the vehicle, Mahaney was so impaired as to violate the statute. The Commonwealth was unable to prove beyond a reasonable doubt, either directly or by permissible inference, the necessary relation between when Mahaney was driving and when he consumed the alcohol.
Mahaney did not challenge the admissibility of his pre-Miranda admission that he was operating the vehicle at the time of the accident nor his post-arrest statement that he had been drinking, thereby waiving these issues for purposes of appeal. We note, however, that until the Commonwealth established the commission of a crime through independent evidence, Mahaney’s admissions could not have been used against him. Commonwealth v. Stoltzfus, 462 Pa. 43, 337 A.2d 873 (1975). In a similar case factually distinguishable from the case at bar, Commonwealth v. DeLeon, 276 Pa.Super. 36, 419 A.2d 82 (1980), the admission of such statements was the dispositive issue. Unlike DeLeon, the facts in this case do not strongly support the inference of an unlawful act as opposed to an accident. I question whether the Commonwealth was able to make out a prima facie case without using Mahaney’s admissions. *138However, in the posture before us on appeal, I have no doubt that the Commonwealth was unable to prove the crime charged beyond a reasonable doubt.
The majority correctly notes that circumstantial evidence is sufficient for a criminal conviction. Inferences are circumstantial evidence. However, inferred facts must follow beyond a reasonable doubt from proven facts. Commonwealth v. Sojourner, 268 Pa.Super. 472, 408 A.2d 1100 (1979). In this case there are too many variables and too few corroborating facts in the evidence to support the inferences necessary to a verdict for the Commonwealth. Mahaney’s conviction rests on an inference that he was intoxicated at the time he was driving the car, specifically at the time of the accident. However, the facts proven do not lead inescapably to this inference and, in fact, do not support it. Therefore, it was not possible for the jury to convict Mahaney beyond a reasonable doubt.
The Commonwealth proved that the accident had occurred by 1:56 a.m. and that it was unlikely to have occurred earlier than midnight. There were no witnesses to the accident or to the manner in which the car was operated. Mahaney admitted to driving the vehicle at the time it was involved in the accident, thus satisfying the first element of the crime. He further admitted that he had consumed two scotches with dinner at approximately 6:30 the previous evening. A blood test taken at 4:00 a.m. showed a blood alcohol level of .17 percent which the Commonwealth’s expert equated with consumption of five to nine ounces of alcohol. It was the expert’s testimony that a blood alcohol level of .17 percent would render the operation of a motor vehicle unsafe. Mahaney did not dispute that he was intoxicated at 2:00 a.m. The foregoing comprised all of the relevant direct evidence presented by the Commonwealth.
The record supports a finding that the accident occurred sometime after the post-midnight patrol of Officer McGinley and before 1:56 a.m. when McGinley was called to the scene. The majority finds an inference that the accident happened shortly before McGinley’s arrival and bases this *139on two facts: that the highway on which the accident happened was routinely patrolled and that debris remained in the roadway. However, this inference does not follow from the evidence. Officer McGinley, whose job included the routine patrolling of that roadway on the evening in question, made only one pass down the highway, shortly after midnight. There is no indication in the record as to any other patrolling done by any other officer or department. Therefore, if the highway was “routinely patrolled”, the record shows that routine to have encompassed at least a two hour time frame. Further, since it is the police investigating an accident who arrange for accident debris to be removed, the fact that debris remained until after police arrived is not remarkable and only further weakens the argument that the highway was routinely patrolled. Neither of these facts cited by the majority, nor the inference claimed as arising from them, do anything to narrow the nearly two hour range of time established by the record during which the accident could have happened.
To leap from this point to a finding that the issue of whether Mahaney was under the influence while he was operating the automobile is one of credibility effectively substitutes a determination of credibility for proof beyond a reasonable doubt. To say, as the majority does, that “there was expert medical testimony consistent with a jury finding that appellant could have been under the influence of alcohol as early as 12:00 midnight” (emphasis added) evidences speculation, not inference, and cannot legally support a finding of guilt where neither physical condition at the critical time nor the time of the violative act is proven beyond a reasonable doubt. Similarly, the inference of intoxication the majority claims, without citing any support, from the “mere occurrence of appellant’s accident” is not based on proven facts. To find these sufficient to meet the requisite standard of proof in a criminal matter is to improperly raise a determination of credibility coupled with an arguably questionable permissible inference to the level of conclusive proof and relieve the Commonwealth of its burden.
*140It is undisputed that Mahaney did not drink after 2:00 a.m. and, therefore, according to the rate of dissipation of approximately .02 percent per hour testified to by the expert, the Commonwealth in entitled to the inference that Mahaney’s blood level at 2:00 a.m. was at or about .21 percent. Again according to the expert’s testimony, the two scotches with dinner would have been completely dissipated by 12:30 p.m. and could not have accounted for any part of Mahaney’s blood alcohol level at 2:00 a.m.1 Therefore, the Commonwealth proved by inference no more than the fact that Mahaney consumed more alcohol than the admitted two scotches with dinner. Mahaney confirmed this in his testimony that after the accident and while waiting for help, he consumed four and one-half twelve ounce beers given to him by a friend whose help he sought following the accident. This friend corroborated Mahaney’s testimony by confirming that he gave Mahaney the beer after the accident and that Mahaney was not intoxicated when he came to the door shortly after the accident.
While the jury, as it was free to do, obviously did not believe Mahaney’s testimony that he drank after the accident, the Commonwealth relied solely on Mahaney’s admissions and produced no evidence to show that he consumed any alcohol at any time. Consumption of the admitted number of beers on an empty stomach would, according to the expert, result in a rapid absorption which would be complete within two hours. Therefore, if the jury accepted Mahaney’s admission of that consumption as it apparently did, it must follow that without knowing when he drank, it was impossible for the jury to allow for any attendant rise *141in blood alcohol level that might have accounted for some part of the inferred .21 percent level at 2:00 a.m.
In my dissent in Commonwealth v. Slingerland, 358 Pa.Super. 531, 518 A.2d 266 (1986), I observed:
[B]ecause of the “commonly known fact that the percent of blood alcohol is not static but varies constantly according to the time elapsing after initial ingestion,” Commonwealth v. Kostra, 349 Pa.Super. 89, 99-100, 502 A.2d 1287, 1292 (1985), there was no reliable way for the jury to determine beyond a reasonable doubt from the test results what the defendant’s blood-alcohol level was when he drove. Id., 358 Pa.Superior Ct. at 537, 518 A.2d at 269.
Here, as in Slingerland, “no one observed the defendant driving and the only evidence pertaining to that time period was the fact that he had an accident, which by itself was not sufficient to relate his blood-alcohol level back to the time of operation.” Id., 358 Pa.Superior Ct. at 540, 518 A.2d 271 (Cirillo, P.J., dissenting). See also Commonwealth v. Griscavage, 336 Pa.Super. 141, 485 A.2d 470 (1984); Commonwealth v. Arizini, 277 Pa.Super. 27, 419 A.2d 643 (1980).
The Commonwealth proved only that his blood alcohol level two or more hours after the the accident was sufficient to impair his driving had he been operating a motor vehicle at that time. The Commonwealth did not use its expert to show the probable level of intoxication at any time other than 4:00 a.m.; therefore, Mahaney’s probable level of intoxication during the range of time established for the accident was not only not proven, there was no evidence offered on that point. Proof of his level of intoxication at the time of investigation is not proof beyond a reasonable doubt of his intoxication at the time he was driving.
Unlike the situation in Commonwealth v. Speights, 353 Pa.Super. 258, 509 A.2d 1263 (1986), there is in this case no strong contemporaneous evidence corroborating the defendant’s operation of the vehicle while intoxicated. This fallacy in the Commonwealth’s case is fatally compounded by *142the Commonwealth’s failure to prove when the accident happened. This is the only point at which Mahaney’s condition is relevant and, since no more than a range of time was established, it was impossible to conclude beyond a reasonable doubt that Mahaney was sufficiently impaired at the critical time.
The Commonwealth offered no corroborating evidence that would entitle it to the inference that Mahaney drank before driving. Commonwealth v. Bruder, 365 Pa.Super. 106, 528 A.2d 1385 (1987) (allocatur pending). Similarly, there are no proven facts from which it can, beyond a reasonable doubt, be inferred that Mahaney was intoxicated when the accident happened. This is pure speculation and is an improper basis for the jury’s verdict. A verdict may not be supported where the jury must guess at any essential fact in favor of a party having the burden of proving it. DiGiannantonio v. Pittsburgh R. Co., 402 Pa. 27, 166 A.2d 28 (1960); Cuthbert v. Philadelphia, 417 Pa. 610, 209 A.2d 261 (1965). This is especially true where the burden of proof is greater than by the preponderance of evidence. Koeune v. State Bank of Schuylkill Haven, 134 Pa.Super. 108, 4 A.2d 234 (1939).
The circumstantial evidence presented in this case proves only appellant’s intoxication at the time of investigation, which Mahaney freely admits, not at the time of the accident. The range of approximately two hours established by the Commonwealth for the occurrence of the accident required the jury to guess as to an essential element of the Commonwealth’s case, namely, whether appellant was under the influence while he was operating the vehicle. The fact that the jury disbelieved Mahaney’s testimony and that of his friend does not prove beyond a reasonable doubt that appellant was sufficiently impaired before the accident.
Contrary to the standard in Commonwealth v. Arizini, 277 Pa.Super. 27, 419 A.2d 643 (1980), cited by the trial court, the nexus between consumption of alcohol and operation of the vehicle required to support a violation of 75 Pa.C.S. § 3731(a)(1) was not established in this case. The *143Commonwealth proved conclusively only that Mahaney was too intoxicated at the time of the investigation to drive safely. However, since the Commonwealth had the burden of proving that while he was operating the vehicle Mahaney was under the influence of alcohol to a degree that rendered driving unsafe, in order to do so it must prove, beyond a reasonable doubt, when he was driving. The majority’s conclusion that the Commonwealth was entitled to the inference that Mahaney was driving while intoxicated clearly reaches well beyond the proven facts and logical inferences therefrom.
Without proving either the time of consumption or the time of operation, the Commonwealth could not prove beyond a reasonable doubt the second element of the offense charged. Even viewed in the light most favorable to the Commonwealth, the evidence in this case is just as consistent with innocence as it is with guilt. Because the Commonwealth could show only that the accident occurred between midnight and 2:00 a.m. and because it could not prove, even by inference, at what point in time Mahaney was drinking, nor how intoxicated he might have been at any given point within that time period, the Commonwealth’s burden was not satisfied and the conviction should be reversed.
. Accepting the expert’s testimony that .17 percent represented five to nine ounces of alcohol and assuming that one scotch contained one ounce, each of the drinks Mahaney admitted having earlier in the evening would have increased his blood alcohol level between .018 percent and .034 percent when fully absorbed. On a full stomach, such as Mahaney would have had after dinner, these drinks would have been fully absorbed by 10:00 p.m. when his blood alcohol level would have ranged between .036 percent and .068 percent. Using a factor of .02 percent dissipation per hour, Mahaney’s blood alcohol level attributable to these drinks at midnight could have been no more than .008 percent.