Appellant's house burned in 1976. Appellee insurance companies brought this diversity action claiming arson and seeking a declaration that they were not liable for the loss. The jury made a special finding of arson. Appellant cites as error the district court's ruling on an evidentiary point, on a proposed jury instruction, and on appellant's motion for a mistrial. We affirm.

The evidentiary ruling was made at the close of plaintiffs' case. Appellant moved to strike the opinion testimony of a state fire marshal, Ricker, that the fire was of human origin because part of Ricker's opinion had been based on information from other fire marshals on the inspection team that the furnace or heating system was not the cause of the fire.1 It appears that Ricker had made his own observations of a lawnmower on which burned fragments of wood had fallen from above, suggesting that the fire had not started in the basement, this tending to rule out the furnace as the source; he had also observed in the basement oil tanks two-thirds or three-quarters full; he had eliminated other possible causes the sun's rays, lightning, spontaneous combustion, electrical wiring; one complete candle had been found, as well as a wrapper devised for two candles, and other items of circumstantial evidence. Ricker also relied on the statements referred to in the motion to strike from his team members, who were more experienced in inspecting oil burners.

The district court's refusal to strike Ricker's testimony was fully justified by Federal Rule of Evidence 703.2 Even more illuminating, in the light of the facts of this case, are the accompanying advisory notes, which read in part:

"Facts or data upon which expert opinions are based may, under the rule, be derived from ... presentation of data to the expert outside of court and other than by his own perception. In this respect the rule is designed to broaden the basis for expert opinions beyond that current in many jurisdictions and to bring the judicial practice into line with the practice of the experts themselves when not in court. Thus a physician in his own practice bases his diagnosis on information from numerous sources and of considerable variety, including statements by patients and relatives, reports and opinions from nurses, technicians and other doctors, hospital records and x rays. Most of them are admissible in evidence, but only with the expenditure of substantial time in producing and examining various authenticating witnesses. The physician makes life-and-death decisions in reliance upon them. His validation, expertly performed and subject to cross-examination, ought to suffice for judicial purposes." (Emphasis added.)

Appellant conceded Ricker's expert qualifications. Ricker testified that his conclusions were based upon his own investigation of the ruins together with reports from his coinvestigators Bissett and Rollins with whom he said he worked as a "team". Since it is reasonable for one state fire marshal to rely on the contemporaneous and on-the-scene opinions of other investigators on his team as to the portion of the investigation that they carried out within their competence, Ricker's testimony was properly admitted. Fed.R.Evid. 703.3 The important requirement that reliance be reasonable a matter requiring the district court's careful consideration was amply satisfied in this case.

Appellant next objects that the district court only charged the jury that proof of arson must be "clear and convincing", not that it need be "clear, convincing, and unequivocal ". A dictum in one recent Maine case does alternate this three part formulation with the standard's more traditional and concise two-adjective phrasing. See Horner v. Flynn, 334 A.2d 194, 199, 200 (Me.1975). Given the district court's explicit effort to comply with Horner's general thrust rather than its "particular words or phrases" and appellant's own failure to articulate what content "unequivocal" would add to the charge, cf. Webster's Third New International Dictionary 2494 (1963) (defining "unequivocal" as "clear"), we regard the omission as an admirable, if minor, blow against tautology.

Finally appellant complains of an allegedly improper statement in appellees' closing argument. Our review of this point is precluded by appellant's own tactical decision at trial. The day after closing arguments but before the jury retired to deliberate, appellant stated his concern that appellees' improper argument in closing might require a mistrial. The district court said "Let's have it now. If you are to move for a mistrial, this is the time. Maybe it should have been after the argument." Without objection appellant withdrew his motion for mistrial.

Affirmed.