(dissenting in part)—I disagree with the majority insofar as it reverses the trial court's determination for assessment years 1963-1967 (i.e., tax years 1964-1968). I concur with the balance of the opinion. Thus, I would affirm the trial court in toto.
I dissent even though I accept the following factual recitation made by the majority: (1) The leaseholds of appellant, the Olympic Hotel and University Properties, Inc., have similar characteristics making valuation comparisons valid on the constitutional issues of discrimination and *389uniformity; (2) during assessment years 1968-69 (i.e., tax years 1969-70) the available record of valuation techniques demonstrates that appellant was unconstitutionally discriminated against based on the uncontested fact that mortgage payment deductions were allowed in those 2 years to University Properties, Inc., while no similar deductions were granted when valuing appellant's leasehold and improvements; (3) the Olympic Hotel and University Properties, Inc., were assessed in a substantially different manner than was appellant during assessment years 1963-67; (4) the county did not preserve the record which might explain valuation techniques utilized for the Olympic Hotel and University Properties, Inc., for assessment years 1963-67.
I also agree property tax assessments and underlying valuations are presumed valid. Thus, the appellant has the burden to establish, by clear and convincing evidence, that the assessor's valuations either were fraudulently, arbitrarily, or capriciously made or violate some constitutional provision. Here, appellant simply has not satisfied its burden for assessment years 1963-67.
Appellant points to no substantive evidence that establishes either that the assessor's valuations were fraudulently, arbitrarily, or capriciously made, or that they violate some constitutional provision. Indeed, even the majority opinion points to no such evidence. In the absence of such proof, appellant has neither sustained its heavy burden of proof nor met the rebuttable presumption of validity which attaches to property tax assessments and valuations. Baker v. Lake City Sewer Dist., 30 Wn.2d 510, 191 P.2d 844 (1948); School Dist. 88 v. Morgan, 147 Wash. 321, 266 P. 150 (1928). Thus, I cannot agree that "the trial court placed too great an emphasis upon the presumption of proper assessment" thereby committing error.
The majority seeks to excuse appellant's failure of proof by pointing to the county's failure to preserve and produce records which might explain valuation techniques utilized *390during assessment years 1963-67. But, mere failure to preserve such records, standing alone, is not a substitute for the substantive evidence necessary to meet appellant's burden of proof, and neither appellant nor the majority directly so contend.
Yet, the majority and appellant take the position that:
where relevant evidence which would properly be a part of a case is within the control of a party whose interests it would naturally be to produce it and he fails to do so, without satisfactory explanation, the only inference which the finder of fact may draw is that such evidence would be unfavorable to him [the county] . . .
. . . the only inference which may be drawn is unfavorable to the contention of the respondents [the county] that . . . discriminatory techniques were not in fact employed.
(Brackets and italics mine.) Here the majority treats failure to preserve and produce documents as creating a mandatory inference that the contents of the missing documents, if produced, would be unfavorable to the county and would also establish the fact of discriminatory techniques. In this circuitous fashion, the majority seeks to create the missing substantive evidence and thus finds appellant to have satisfied its burden of proof. Support for such an unusual "triple-play" is sought in British Columbia Breweries (1918) Ltd. v. King County, 17 Wn.2d 437, 135 P.2d 870 (1943), and its progeny.
I agree with the majority that unexplained failure to preserve and thus produce relevant records in one's possession may create an unfavorable inference rather than an unfavorable presumption. The majority has correctly characterized the evidentiary function served by failure to preserve and produce records thus clarifying some of the confusion generated by British Columbia Breweries. In fact, most authorities agree presumptions and inferences are entirely different. 1 S. Gard, Jones on Evidence § 3:2, at 129 (6th ed. 1972); 9 J. Wigmore, Evidence § 2491 (3d ed. 1940); 31A C.J.S. Evidence § 115, at 198 (1964). A presumption arises from the high degree of probative value stemming from an *391established factual basis and is mandatory until better evidence rebuts it. Kay v. Occidental Life Ins. Co., 28 Wn.2d 300, 183 P.2d 181 (1947); State v. Jukich, 135 Wash. 682, 239 P. 207 (1925); 1 S. Gard, Jones on Evidence §§ 3:1, 3:2, at 125-30; 9 J. Wigmore, Evidence § 2491, at 286-93. An example is the rebuttable presumption of validity attaching to the official acts found in this case. Pierce v. Lake Stevens School Dist. 4, 84 Wn.2d 772, 529 P.2d 810 (1974); see Rosso v. State Personnel Bd., 68 Wn.2d 16, 411 P.2d 138 (1966); State ex rel. Longview Fire Fighters Local 828, I.A.F.F. v. Longview, 65 Wn.2d 568, 399 P.2d 1 (1965); E. Cleary, McCormick's Handbook of the Law of Evidence § 343, at 807 (2d ed. 1972). On the other hand, an inference merely may arise as a logical deduction from relevant evidence. Unlike presumptions, inferences do not affect either party's duty to produce evidence. J. Thayer, Preliminary Treatise on Evidence 336-39 (1898); 9 J. Wigmore, Evidence § 2491, at 288. Further, no rule of law attaches to an inference; the trier of fact may give it whatever force or weight it thinks best, just as the factfinder may do with other evidence. 9 J. Wigmore, Evidence § 2491, at 288; 31A C.J.S. Evidence § 115, at 198. Thus, inferences are better considered from the standpoint of relevance the same as other evidence. 1 S. Gard, Jones on Evidence § 3:2, at 127-30; 9 J. Wigmore, Evidence § 2491, at 288; see also 31A C.J.S. Evidence § 115, at 198.
While I agree respondent's unexplained failure to preserve or produce documents may permit an unfavorable inference, appellant has not produced sufficient evidence to make the inference relevant. The unfavorable inference which may arise from the destruction of, or failure to preserve, evidence is only available if the destruction has been wilful, deliberate, or done with some evil intent. Walker v. Herke, 20 Wn.2d 239, 147 P.2d 255 (1944); 1 S. Gard, Jones on Evidence § 3:90, at 319; 29 Am. Jur. 2d Evidence § 177, at 220-21 (1967); 31A C.J.S. Evidence § 153, at 389-90. Even the unfavorable inference which may arise from the possessor's failure to produce evidence is not available if *392the evidence has been accidentally destroyed or lost. 1 S. Gard, Jones on Evidence § 3:93, at 329; 31A C.J.S. § 156(2), at 402. Here, neither inference is appropriate. There is no showing either that the destruction was wilful, deliberate or done with evil intent or that the attendant failure to produce arose other than from accidental destruction or mere loss. The most appellant has shown is that no one knows what happened to the assessor's records. Appellant merely implies that the failure to preserve must have been done wrongfully. This is pure speculation which may not be substituted for substantive proof. The absence of substantive evidence renders the unfavorable inferences unavailable.
The majority next treats the inference as mandatory. I disagree with this evidentiary maneuver for two reasons. First, British Columbia Breweries at page 455 twice uses the expression "the only inference which may be drawn" (italics mine). But, careful review of the entire text plus review of the cited authorities and their later editions makes clear that the inference is not mandatory. Rather, it is permissive only. The trier of fact may draw the inference but is not required to do so. 1 S. Gard, Jones on Evidence § 3:91, at 324, § 3:93, at 327; 31A C.J.S. § 156(1), at 398; Annot., 70 A.L.R. 1326 (1931). Thus, even if the trier of fact here was permitted to draw an unfavorable inference, it chose not to do so. Consequently, the rebuttable presumption that assessments are valid was not negated.
I also disagree with the majority's assumption that the inference would specifically have been "unfavorable to the contention of the respondents [county] that such discriminatory techniques were not in fact employed." (Brackets and italics mine.) British Columbia Breweries does not support this position. In fact, we said at page 455:
The rule is that the only inference which may be drawn by the trier of the fact is that
"... Evidence of such conduct is persuasive rather than probative and cannot be invoked as substantive proof of any facts essential to the case of the opponent. *393The rule has been stated that the presumption [more properly denominated a permissive inference] will not supply a missing link in an adversary's case and cannot be treated as independent evidence of a fact otherwise unproved. It has been stated that the presumption [more properly denominated a permissive inference] arising from the nonproduction of evidence does not relieve the other party from the burden of proving his case."
(Italics mine.)
Neither can the inference relied on here be substituted for substantive proof of discriminatory techniques, nor can it relieve the appellant of the obligation of proving its case. Walker v. Herke, supra.
The inference merely discounts the credibility of the withholding party's claim. Walker v. Herke, supra at 249-51; 2 J. Wigmore, Evidence § 278(2), at 120; 1 S. Gard, Jones on Evidence § 3:90, at 321, § 3:91, at 325, § 3:93, at 329; 31A C.J.S. 156(1), at 399; 70 A.L.R. 1326. It does not substitute for substantive proof of any fact much less take the place of proof of a fact essential to the case of the party invoking it. Walker v. Herke, supra; 1 S. Gard, Jones on Evidence § 3:93, at 329; 31A C.J.S. § 152, at 388, § 156(1), at 398. Further, it does not supply a missing link in the proponent's case because it is not independent evidence of any fact otherwise unproved. 29 Am. Jur. 2d § 178, at 223; 31A C.J.S. § 152, at 388, § 156(1), at 398.
The inference permits the trier of fact to infer that the missing documents would be unfavorable to the claim of the county. But it does not permit the further inference that, if produced, the evidence would establish any specific underlying unfavorable facts. 1 S. Gard, Jones on Evidence § 3:90, at 320-21, § 3:91, at 325, § 3:93, at 329; 29 Am. Jur. 2d § 179, at 224. Nor does it constitute proof of the contents or nature of the documents which it is claimed would have been shown on production. 31A C.J.S. § 156(1), at 398-99. The inference merely diminishes the force of the spoliator's existing evidence or enhances the probative value of that actually produced by his opponent. Olsson v. *394Hansen, 50 Wn.2d 199, 310 P.2d 251 (1957); 31A C.J.S. § 153, at 389-90, § 156(1), at 390, § 152, at 388.
In any event appellant must still establish a prima facie case. Walker v. Herke, supra; 1 S. Gard, Jones on Evidence § 3:93, at 329; 29 Am. Jur. 2d § 177, at 221; 31A C.J.S. § 152, at 388; 70 A.L.R. 1326. Here, appellant has produced no substantive evidence and has established no prima facie case for assessment years 1963-67. Thus, there is nothing to which the inference could attach. Since the inference does not supply the crucial missing link in appellant's case, and since it is not independent evidence of any fact and is neither affirmative nor substantive proof of the content or nature of the missing paper, appellant has failed to sustain its burden of proving by clear and convincing evidence that the challenged valuations and assessments for assessment years 1963-67 are illegal.
For this reason, the trial court having been affirmed on all other points, it should be affirmed in full.