joined by GONZALEZ, Justice, dissenting.
Having canvassed the reported decisions of every jurisdiction in the United States and correctly concluded that none has ever come close to approving a single trial of as many different claims of injury due to exposure to asbestos against as many separate defendants involving as widely disparate allegations as the district court has done in the present ease, the Court still holds that the district court has not been shown to have abused its discretion because defendants did not adduce more proof of likely confusion and prejudice. Requiring additional evidence of confusion and prejudice in mature mass-tort litigation like this is unnecessary. The purpose of the Maryland factors that the Court adopts is to determine when prejudice is likely without a mini-trial before the real trial. If defendants’ evidence of prejudice in this case is weak — I do not think it is— evidence of the possibility of a fair and impartial trial under the consolidation order in this case is scant, and evidence of any real judicial efficiency or economy to be achieved is nonexistent.
Trying multiple claims in a single trial can avoid unnecessary expense and delay without prejudice to the parties. The rules of procedure provide for consolidation as a useful tool for resolving numerous claims involving common issues. But it cannot simply be presumed, as the district court and this Court have done, that consolidated trials are more efficient and non-prejudieial absent evidence to the contrary. Having shown that some prejudice is likely, absent evidence that prejudice is unlikely and that any real efficiency can be achieved, and most especially, absent any supporting authority from any jurisdiction, defendants are entitled to have the consolidation order set aside. Accordingly, I respectfully dissent.
The Court’s impressive survey of case law does not impress the Court itself. The most *618complex consolidation of asbestos claims for trial affirmed on appeal involved the claims of twelve workers and their families against one defendant alleging comparable periods of exposure to one product at various sites over forty years.1 A court that tried the claims of thirteen workers and their families against the same few defendants for exposure to asbestos at a single site granted a motion for new trial following the verdict, concluding that “a process had been unleashed that left the jury the impossible task of being able to carefully sort out and distinguish the facts and law of thirteen plaintiffs’ cases that varied greatly in so many critical aspects.”2 Consistently, the Second Circuit reversed a judgment following trial of forty-eight asbestos plaintiffs against twenty-five defendants, concluding that all efforts by the trial court were “feckless in preventing jury confusion.” 3 The Court summarizes the other cases correctly when it says: “Generally speaking, it seems that the federal courts have met with success in trying five or fewer claims at a time, but that larger numbers of claims in a single trial have presented problems.”4 The outside limit in the reported decisions is twelve claims against one defendant. The only exception proves the rule. The Second Circuit approved trial of sixty-four asbestos exposure cases5 only because ninety percent of the exposure occurred at a single worksite “subject to the uniformity in procurement and practice typical of the Navy”.6 The similarity of the workers’ claims and their exposure to asbestos at a single site under almost identical conditions was crucial to consolidation of the claims for trial.7
Given courts’ experience with asbestos-exposure litigation, it is possible to try more products liability claims together if the claims are similar. But the claims in the case before us are against premises owners, not product manufacturers. Defendants’ knowledge of the health hazards of handling asbestos vary more widely in claims against premises owners than in claims against manufacturers. Not a single reported decision from any court in the United States supports consolidation for trial of twenty-two claims against five premises owners alleging exposure to asbestos on one or more but not all of defendants’ premises, as well as forty-one other work sites, for periods varying from one to thirty-eight years, resulting in injuries ranging from pleural thickening to cancer and death. At least the two decisions disapproving trials of thirteen and forty-eight consolidated claims are to the contrary. The present case with twenty-two consolidated claims against premises owners is far and away the most complex asbestos-exposure ease of record. A court abuses its discretion if it acts ‘“without regard for any guiding rules or principles.’”8 When no authority supports the court’s decision, and all valid authority contradicts it, the court has abused its discretion.
Defendants have shown not only a lack of supporting authority but a lack of supporting evidence. Evidence that a trial of the consolidated claims would be fair and impartial is contained in two affidavits submitted by plaintiffs’ counsel. In one, plaintiffs counsel asserts that he has tried “many consolidated *619asbestos trials over the past seven years, ranging from two or three cases to 289 cases, with an average of 25-30 cases.” The large case, it should be noted, was reversed, albeit on grounds other than consolidation.9 Counsel’s affidavit continues: “It is readily apparent from the verdicts that juries give careful individual attention to each plaintiff and make decisions based on the specific evidence introduced by each party.” Assuming that the verdicts referred to would make counsel’s conclusion readily apparent, those verdicts are not attached to the affidavit or described, other than by counsel’s statement that plaintiffs sometimes won and sometimes lost. This evidence is conclusory and entitled to no consideration. In the second affidavit, plaintiffs’ counsel asserts that he once tried twenty-five claims in a single trial that was obviously fair and impartial because the jury awarded one claimant $3,337,000 and others less, some as little as $50,000. The affidavit does not describe the nature of the claims or their similarities and differences. Thus, it is also conclusory and should be given no weight. The second affiant also asserts that the evidence common to all consolidated claims is the diagnosis of all plaintiffs’ conditions by one of two physicians, Dr. Gary K. Friedman and Dr. Jeff D. Britton — who regularly testify for plaintiffs in asbestos eases10 —and the knowledge of the dangers of asbestos and industry standards for protection from such dangers. These two facts — that plaintiffs will rely on the same experts they often rely on in such cases, and that exposure to asbestos has long been known to be dangerous to health — do not show sufficient similarities between the twenty-two claims to justify consolidation in a single trial.
Defendants’ evidence that a single trial will not be fair is substantial and uneontroverted. Defendants’ expert, a psychologist and jury consultant, identified nine differences in plaintiffs’ claims that would make it difficult for jurors to separate the evidence as to each plaintiff. The expert testified that joining so many plaintiffs in a single trial would influence jurors to find liability and award damages to all plaintiffs when they would not do so otherwise. Defendants submitted exhibits detailing plaintiffs’ work histories and exposures to asbestos. In hearings before the district court, plaintiffs’ counsel did not take issue with defendants’ counsel’s description of the differences in plaintiffs’ allegations and evidence regarding plaintiffs’ work sites, occupations, times of exposure, and types of disease. Defendants’ assertions in motions and hearings that such differences prevent a fair and impartial trial of the twenty-two consolidated claims stand unchallenged by plaintiffs.
The only evidence of efficiency to be achieved by consolidation of twenty-two claims for trial is plaintiffs’ counsel’s assertion in his affidavit that the consolidated case can be tried in twenty days as compared with eight or nine days apiece to try each claim separately. Of course, consolidating twenty-two claims and trying each claim separately are not the only two alternatives. Nothing in the record indicates that the district court assessed the risk of wasted time and money to the parties and the court if the trial eventually proved to be prejudicial and unfair, or that the court considered the benefits of trying fewer or more similar claims with less risk of prejudice. The court did not explore trying a few typical claims in smaller groups to obtain verdicts that could serve as a basis for settling similar claims. The court did not consider whether evidentiary disputes could be reduced after such trials so as to shorten future proceedings. The only issue the court addressed was how many claims to try at *620once, and the presumption implicit throughout the hearings before the court was that the more claims that are tried together, the better. The court indicated that after this consolidated trial, the next batch of claims set for trial would be larger.
Obviously, if claims can be tried together in less time than they can be tried separately without prejudice to the parties, then it is more efficient to do so. Rule 174(a) of the Texas Rules of Civil Procedure authorizes consolidation of claims for trial “as may tend to avoid unnecessary costs or delay.” But as the risk of prejudice grows due to the confusion in trying multiple claims at once, possible efficiencies of consolidated trials diminish. The burden on the parties and the system caused by reversal on appeal must be considered. As the Court emphasizes, “The rights of the parties to a fair trial cannot be compromised in the name of judicial economy.” 11
In determining the number of claims to consolidate, a court can certainly take into consideration the possibility that some might settle before trial actually commenced, although there is no indication in the present case that the court did so. But as the Court indicates, it would be improper for excessive numbers of claims to be consolidated merely to coerce settlements. Economy cannot be achieved by threatening to try so many claims at once that parties must settle rather than risk long trials and appeals.
Absent any evidence of real economy to be served by consolidating twenty-two claims for trial, absent any showing of how those claims can be tried together without prejudice to defendants, absent any authority from any jurisdiction approving so large a consolidation of such disparate claims, given some contrary authority, and given defendants’ un-rebutted assertions of prejudice, defendants are entitled to have the consolidation order set aside. To require more evidence of prejudice, as the Court does, encourages more extensive pretrial hearings — mini-trials before trial — to preview the evidence and determine the possibilities of prejudice. In immature mass-tort litigation such hearings may be necessary, but asbestos-exposure litigation is well enough developed that such hearings should not be necessary. Indeed, the Maryland factors that the Court applies are distilled from the experience of a number of courts in asbestos-exposure litigation.12 The purpose of the factors is to identify differences in typical asbestos claims that can result in prejudice and confusion if the claims are tried together. The exhibits to defendants’ motion in this case detailing the plaintiffs’ various occupations, work sites, times of exposure, and diseases make the likelihood of prejudice, in light of the Maryland factors, apparent.
Burgeoning caseloads demand ever more efficient management and disposition techniques, lest the expense and delay of litigation result in a justice system that is unsuited for the very task for which it exists: resolving disputes. But as important as efficiency has become to the justice system, it is not as important as justice itself. Achieving justice in mass-tort litigation requires a careful balancing of legitimate, competing interests: the plaintiff’s interest in a reasonably timely resolution of his claim, and the defendant’s interest in a fair and impartial trial. From the fact that a number of consolidated asbestos-exposure cases have been tried in Texas and to date appeals have been few, the Court infers that such trials are generally being conducted without prejudice. If that inference is legitimate, today’s opinion should encourage trial courts to use care in consolidating cases for trial to minimize prejudice. Despite the Court’s denial of relief in this case, it should be clear from the Court’s application of the Maryland factors that when defendants adduce the evidence the Court finds lacking, the prejudice in trying the twenty-two claims together will be established. The district court would do well to reconsider its consolidation order in light of today’s opinion rather than to rely entirely on today’s judgment.
. Owens-Corning Fiberglas Corp. v. Martin, 942 S.W.2d 712 (Tex.App.—Dallas 1997, no writ).
. Cain v. Armstrong World Indus., 785 F.Supp. 1448, 1457 (S.D.Ala.1992).
. Malcolm v. National Gypsum Co., 995 F.2d 346, 352 (2d Cir.1993).
. Ante at 612.
. In re E. and S. Dists. Asbestos Litig. (Brooklyn Navy Yard), 772 F.Supp. 1380 (E. & S.D.N.Y. 1991), aff'd in part and rev’d in part sub nom. In re Brooklyn Navy Yard Asbestos Litig., 971 F.2d 831 (2d Cir.1992).
. Malcolm, 995 F.2d at 353. See also Consorti v. Armstrong World Indus., Inc., 72 F.3d 1003, 1006 (2d Cir.1995) (observing that the consolidation in the Brooklyn Navy Yard litigation "would have passed muster”), vacated on other grounds, 518 U.S. 1031, 116 S.Ct. 2576, 135 L.Ed.2d 1091 (1996).
. Malcolm, 995 F.2d at 353 (emphasizing that "[b]ecause uniformity is a way of life with the military, the commonality of the ... cases cannot be overstated.").
. Owens-Corning Fiberglas Corp. v. Malone, 972 S.W.2d 35, 43 (Tex.1998) (quoting City of Brownsville v. Alvarado, 897 S.W.2d 750, 753 (Tex. 1995)).
. Owens-Illinois, Inc. v. Chatham, 899 S.W.2d 722 (Tex.App.—Houston [14th Dist.] 1995, writ dism’d).
. See, e.g., Whatley v. Armstrong World Indus., Inc., 861 F.2d 837, 844 (5th Cir.1988); Smith v. A.C. & S., Inc., 843 F.2d 854, 856 (5th Cir.1988); Cole v. Celotex Corp., 599 So.2d 1058, 1075 (La. 1992); Owens-Illinois, Inc. v. Chatham, 899 S.W.2d 722, 726 (Tex.App.—Houston [14th Dist.] 1995, writ dism’d); Srite v. Owens-Illinois, Inc., 870 S.W.2d 556, 560-563 (Tex.App.—Houston [1st Dist.] 1993), rev'd sub nom. Owens-Illinois, Inc. v. Estate of Burt, 897 S.W.2d 765 (Tex.1995); Fibreboard Corp. v. Pool, 813 S.W.2d 658, 681-682 (Tex.App.—Texarkana 1991), cert. denied, 509 U.S. 923, 113 S.Ct. 3037, 125 L.Ed.2d 724 (1993); Pecorino v. Raymark Indus., Inc., 763 S.W.2d 561, 575 (Tex.App.—Beaumont 1988), on reh’g, 766 S.W.2d 316 (Tex.App.—Beaumont 1989, no writ).
. Ante at 610.
. In re All Asbestos Cases Pending in the United States District Court for the District of Maryland (D.Md. Dec. 16, 1983) (en banc) (cited in Malcolm v. National Gypsum Co., 995 F.2d 346, 351 (2d Cir.1993)).