dissenting.
Because plaintiffs were not entitled to rely on res ipsa loquitur, the court’s refusal to instruct the jury was not an error. Further, I am not convinced that, when res ipsa loquitur does apply, the court should ever give a jury instruction on the inference of negligence. Accordingly, I dissent.
Res ipsa loquitur is a rule of circumstantial evidence that allows an inference of negligence to be drawn if the accident is of a kind which ordinarily would not have occurred in the absence of the defendant’s negligence, even though it might be impossible to determine the specific way in which the defendant was negligent. Watzig v. Tobin, 292 Or 645, 642 P2d 651 (1982); Kaufman v. Fisher, 230 Or 626, 371 P2d 948 (1962). Before res ipsa loquitur can apply, the plaintiff must show that the defendant had exclusive control of the instrumentality. That does not mean that the defendant must be in exclusive physical possession. Instead, it must be clear that the defendant’s negligent actions are in all probability the cause of the plaintiffs injury. Pattle v. Wildish Construction Co., 270 Or 792, 797, 529 P2d 924 (1974). Res ipsa loquitur does not apply in this case, because defendant did not have exclusive control over the instrumentality. Sewers become plugged and back up even when municipalities are exercising reasonable care.
This case is controlled by Jordan v. Hillsboro, 48 Or App 839, 617 P2d 970 (1980), and Hamilton v. State, 42 Or App 821, 601 P2d 882 (1979). In both, we held that the plaintiffs were not entitled to argue res ipsa loquitur, because the defendants did not have exclusive control over the sewer system, which was the instrumentality.1 In Jordan, the *34plaintiffs home was damaged when a sewer backed up due to large amounts of muddy water in the system. Several pipes were damaged at the site of a new housing development, and run off had entered the system through the broken lines. Similarly, in Hamilton, unknown third parties had placed large rocks inside a maintenance hole, causing it to overflow and damage the plaintiffs home.
The majority places undue emphasis on the fact the sources of the obstructions in Jordan and Hamilton were suspected negligent or wilful conduct by third parties. In my view, the holdings do not turn on the fact that there was strong evidence of interference by third parties. The evidence of third party contribution only bolstered the critical fact that the defendants did not have exclusive control because of the potential for access by third parties.
Other jurisdictions, when faced with cases on similar facts, have also held that res ipsa loquitur does not apply. For example, in Reich v. Salt Lake City Suburban Sanitary Dist. No. 1, 29 Utah 2d 125, 506 P2d 53 (1973), a main sewer line became plugged, forcing raw sewage up through the drains and toilets of the plaintiffs’ homes. There was no evidence as to what caused the obstruction or the resulting flooding. Nevertheless, the Utah Supreme Court held that the plaintiffs could not argue res ipsa loquitur, because the defendant did not have exclusive control over the system. That particular system was connected to 270 homes as well as over to 100 unlocked maintenance holes:
“Rags, garbage, bones, sanitary napkins, diapers, and any number of other items could pass through laterals of a diameter of four inches. If these items flocculate together and a blockage occurs, it cannot be held that the defendant is liable under the rule of res ipsa loquitur.” 29 Utah 2d at 127.
*35See also City of New Smyrna Beach v. McWhorter, 418 So 2d 261 (Fla 1982); Arey v. Board of Light & Water Com’n, 50 NC App 505, 274 SE 2d 268, rev den 302 NC 629 (1981); Shipley v. City of Spearfish, 89 SD 559, 235 NW 2d 911 (1975); Freitag v. City of Montello, 36 Wis 2d 409, 153 NW 2d 505 (1967).
I am not disputing that res ipsa loquitur requires only that the accident “speak” of the defendant’s negligence; it need not “scream” it. See Kaufman v. Fisher, supra. Neither must a plaintiff eliminate with certainty all other possible causes of the injury, other than the defendant’s negligence. Nevertheless, a plaintiff must be able to show that it is reasonable to infer that the accident would not have happened had the defendant not been negligent. Because numerous users had access to the sewer in this case, defendant did not have exclusive control of the instrumentality. It follows that plaintiff could not demonstrate a strong probability that it was the conduct of defendant, rather than someone else, that caused the injury. Jivelekas v. City of Worland, 546 P2d 419 (Wyo 1976);2 see also Ward v. City of Charlotte, 48 NC App 463, 269 SE 2d 663, rev den 301 NC 531 (1980); Village of Willoughby v. Malone, 171 NE 402 (Ohio 1930).
Because res ipsa loquitur does not apply, the trial court did not err in striking allegation 4 from plaintiffs’ complaint. It merely contained background allegations for the res ipsa loquitur claim. The specific allegation of negligence — that defendant’s employees negligently unstopped a clogged sewer — was sufficiently covered in allegation three.
In my view, we need not decide whether a jury instruction should ever be given when res ipsa loquitur does apply. Although Richie v. Thomas, 190 Or 95, 113, 224 P2d 543 (1950), unequivocally holds that a jury instruction is *36appropriate, recent cases have cast doubt on that holding. For example, in McKee Electric Co. v. Carson Oil Co., 301 Or 339, 723 P2d 288 (1986), the Supreme Court declined to decide whether a res ipsa loquitur instruction should ever be given. 301 Or at 356. Res ipsa loquitur is merely a rule of circumstantial evidence that permits a rational evidentiary conclusion to be drawn from proven facts. The Supreme Court has held that rules of circumstantial evidence are not proper subjects for jury instructions, largely because an instruction on an inference is tantamount to a comment on the evidence. See, e.g., State v. McCormick, 280 Or 417, 571 P2d 499 (1977).
I dissent.
The majority incorrectly identifies the sewage as the “instrumentality,” *34because it caused the actual damage to plaintiffs’ home, relying on Cummins v. City of West Linn, 21 Or App 643, 563 P2d 455 (1975). I believe that that aspect of Cummins has been impliedly overruled by Jordan and Hamilton. Those cases, as well as every other case cited in this dissent, identify the sewer system itself as the instrumentality for the purpose of res ipsa loquitur analysis. It simply does not make any sense to consider sewage as the instrumentality; it is not designed, created or controlled by the municipality. When an accident occurs due to a ’municipality’s negligence, the fault lies in improper design, construction or maintenance of the pipe system — not in the content of the sewage. There is no liability when a municipality is not negligent in constructing or maintaining a system, but a plug occurs due to some unusual content in the sewage.
Jivelekas involved a plugged sewer line that caused sewage to back up into the plaintiffs’ homes. There was testimony that there was no way to prevent a sewer from becoming obstructed by foreign objects. An expert testified for the defendant city:
“Q. What has your experience or familiarity shown you?
“A. All sorts of things are found in the sewer lines. The Denver system has their meat packing areas and have had cows [sic] heads, steers [sic] heads, coming down the sewer lines, tremendous limbs. How they get down in the sewer line I have no idea. All sorts of materials show up in sewer lines, yes, sir.” 546 P2d at 422.