speed measurement is also a matter for impeachment.
Evidence based on scientific measurement may pose difficulties not presented by eyewitness testimony. In particular, a court must contemplate the possibility that the mere introduction of "scientific" or other metric evidence may create an impact upon the jury such that the evidence cannot be effectively impeached.
First, the measurement technique may be highly sophisticated in contrast to the simplified output of the device. Examples of such techniques might be neutron activation analysis or radar. The jury may readily understand the output, e.g., speed, but impeachment based on the measuring technique itself, e.g., the Doppler effect, may be disproportionately difficult to comprehend.
Second, the device may be used so infrequently that the range of accuracy may be totally outside a layman's experience. For instance, a juror may accept a radar speed-gun reading of 50 m. p. h. as absolutely accurate, rather than accurate to plus or minus 5 m. p. h. Conversely, a normal fact trier reasonably may be expected to know that watches or commonly used instruments, like speedometers, are subject to some inaccuracy. Thus, even if a juror does not understand the inner workings of a watch, he will be receptive to evidence of inaccuracy. See J. Wigmore, supra note 2, § 220, at 450 (instruments such as telephone, thermometer, and theodolite, used commonly "without controversy or doubt" require no foundation).
Third, although based upon established techniques, the device may be so novel that its manufacturers have not yet ironed out all the wrinkles or its operators have not yet acquired the experience necessary for routinely accurate calibration. Thus, it would be unfair to accord any presumption that the device was accurate. In contrast, a watch manufacturer may be fairly presumed to make a reasonably accurate watch and to adjust it with reasonable accuracy before placing it on the market. Likewise, the average watch user may be presumed to set or reset the watch with reasonable accuracy. See id.
A fourth, related reason is that the measurement device may be delicate, subject to environmental influences, or otherwise require adjustment each time it is used. Examples might be a scientific balance, an electronic device which must constantly be recalibrated because of temperature or humidity changes, or a Prather Speed Device. See J. Richardson, supra note 2, § 9.3.
Fifth, a small degree of inaccuracy over a continuous range of calibration might make a vast, quantum difference in the quality of evidence. See J. Wigmore, supra note 2, § 220, at 450 (no foundation needed for certain instruments, especially "where no issue turns on minute accuracy.") For example, a miniscule difference in alignment of a voice spectrograph or neutron activation analyzer could change an expert's testimony on the identity of a voice or batch of chemicals. See generally A. Moenssens & F. Inbau, supra note 2, §§ 9.01-.10, 12.01-.09.
Sixth, evidence which may be sufficiently reliable in a civil case may be suspect when introduced as proof beyond a reasonable doubt in a criminal case. See, e.g., People v. Dusing, 5 N.Y.2d 126, 128, 155 N.E.2d 393, 394, 181 N.Y.S.2d 493, 495 (1959) (untested radar or speedometer evidence is admissible, but insufficient to sustain speeding conviction); 75 Pa.Cons.Stat.Ann. § 3368 (evidence from untested speed-timing device is inadmissible in traffic prosecution).
Seventh, if the particular device is an official, government device and the authenticating testimony is from a government official, then the jury may be swayed disproportionately. This may be one reason that many jurisdictions have passed laws restricting evidence of speed-timing devices in criminal prosecutions. See, e.g., 75 Pa.Cons.Stat.Ann. § 3368 (Purdon 1975).
Eighth, the proponent of the measurement may have better control of evidence of accuracy vel non.
(But federal discovery rules tend to eliminate any advantage on his part.) Finally, in every case, the court should be alert for any peculiarities of the device or technique involved.
Almost all of these factors weigh in favor of the general admission of tachograph evidence. First, a tachograph is a relatively unsophisticated device, working on the same mechanical principles as a speedometer. See Conrad, supra note 2, at 288; N.T. 4.120 (defendants' expert's testimony that "the tachograph is based upon simple concepts of velocity, time and distance"). Thus, a jury could comprehend impeachment of accuracy. For instance, in this case, defendants introduced comprehensible impeachment evidence relative to: resolution of problems due to thickness of the stylus blade, N.T. 3.87-.89; possibly incorrect calibration of the cable which drives the tachometer, id. 3.87-.89, .97-.98, .102-.103; driver tampering, id. 3.90-. 92; incorrect zeroing of the speed recordings, id. 3.92-.93; and other alleged inaccuracies. See, e.g., id. 4.140-.143.
Second, although ordinary fact finders may be unfamiliar with the record portion of a tachograph, it is reasonable to expect them to be familiar with the speedometer portion, and to be receptive to evidence of inaccuracy. This expectation is especially reasonable when, as here, the evidence is that a tachograph works in the same way as a speedometer, see id. 3.66, and that the recording disk's accuracy correlates with that of the tachograph speedometer. See id. 3.75.
Third, even assuming that tachograph evidence was novel in 1959, see Bell, 323 S.W.2d at 426, it is by now old hat. In addition to the cases cited above, tachograph evidence has been accepted (without comment) in dozens of cases.
The principles used in the Sangamo tachograph in this case are exactly the same as those described for the Sangamo tachograph pictured in Conrad's 1953 article. See Conrad, supra note 2.
Fourth, the tachograph is a sturdy mechanical device which need not be recalibrated for each use. Fifth, both the tachograph's output and the expert's opinion embraced a continuous scale of speed. A small error in adjustment would result in a proportionate, rather than quantum, change in output. In fact, defendant's own expert used this principle in calculating a correction factor, see N.T. 4.146, which enabled him to use the tachograph to check his opinion.
All but one of the remaining factors weigh in favor of admissibility without foundation. The tachograph here was a private instrument, not backed by police testimony. This is a civil case, rather than a prosecution for a traffic violation.
Here, the opponent of the tachograph had control of the evidence.
One peculiarity of tachographs, however, weighs in favor of a foundation. The tachograph generally is not a piece of original equipment made by the truck manufacturer. The tachograph (of which Sangamo is the only major American manufacturer, N.T. 3.70), is installed separately, and replaces the normal speedometer. N.T. 3.66. Although Sangamo calibrates the instrument internally, Id. 3.89, accurate operation depends on receipt of proper input from the truck rotor cable. Id. 3.74-.75. If the rotor cable does not turn at the correct rate (1,000 turns per mile), a ratio adapter must be installed. Id. 3.90. There was no direct evidence that the rotor cable revolved at the proper rate.
On balance, however, this peculiarity is not enough to outweigh the other factors. The most important of those are the first four: a tachograph operates on simple, understandable principles, removed from the frontiers of science; the range of accuracy of the key portion the speedometer is within the experience of most jurors; there is great experience in its manufacture, operation, and use as evidence; and by its nature, it does not require frequent adjustment. I therefore hold that, in this case, accuracy of the particular tachograph was a matter of impeachment going to the weight of the evidence, rather than a matter of foundation.
See, e.g., NLRB v. Pacific Intermountain Express Co., 228 F.2d 170, 172 (8th Cir. 1955), cert. denied, 351 U.S. 952, 76 S. Ct. 850, 100 L. Ed. 1476 (1956); People v. Dusing, 5 N.Y.2d 126, 128, 155 N.E.2d 393, 394, 181 N.Y.S.2d 493, 495 (1959); State v. Dantonio, 18 N.J. 570, 580-81, 115 A.2d 35, 40-41 (1955); Nicholas v. Penny, (1950) 2 KB 466, 473-74 .
2. Foundation in This Case
Because of the split of authority on the question whether a foundation is necessary, I shall also decide whether, if a foundation was required, it was laid in this case. I hold that it was not.
The substantial question as to accuracy of defendants' tachograph is that discussed above was the rotor cable properly calibrated at 1000 r. p.m.? See text preceding note 8 supra. Plaintiffs had evidence showing reasonable accuracy on all other significant points. For instance, the tachograph was internally calibrated, N.T. 3.89; it had not been tampered with, id. 3.90-.92; and errors due to wear of the stylus blade or its moving off zero were resolved in defendants' favor. Id. 3.108. There was no testimony as to the calibration, no independent test of the tachograph, and no "proof line" test as in Villegas. See 16 Ariz.App. at 458, 494 P.2d at 63. Because accuracy depended on the correct alignment of the cable, and no significant competent evidence supported correct alignment, no foundation was laid for the accuracy of the particular instrument.
3. Harmless Error
Even if the tachograph testimony was admitted erroneously, it was harmless for three reasons. First, the impact speed measured by the tachograph is compatible with the impact speed propounded by defendants. Compare N.T. 3.80 (41-42 m.p.h. measured by tachograph), with id. 4.150 (32-45 m.p.h. estimated by defendants' expert). Second, plaintiff's expert, independent of the tachograph, reconstructed the speed at impact as 43-49 m.p.h. Id. 3.146. Thus, the tachograph output roughly corroborated independent evidence of speed from two other sources. Finally, and most importantly, the impact speed was only tangentially relevant to the ultimate factual question who was in the wrong lane. See id. 5.136.
This accident occurred only because one driver strayed out of his lane of traffic and onto the other side of the road. Under Pennsylvania law, driving on the wrong side of the road without an "excuse" is per se negligent. Mihalic v. Texaco, Inc., 377 F.2d 978, 981 (3d Cir. 1967); Matkevich v. Robertson, 403 Pa. 200, 202-03, 169 A.2d 91, 93 (1961); see Kenworthy v. Burghart, 241 Pa.Super. 267, 277-82, 361 A.2d 335, 340-43 (1976), appeal dismissed, 478 Pa. 20, 385 A.2d 975 (1978).
In this case, each driver claimed the other was on the wrong side, and neither offered an "excuse." Thus, whoever was on the wrong side was negligent. At the request of both parties, I so instructed the jury, N.T. 6.25, without objection.
The significance of defendants' speed was secondary. It provided plaintiff with a theory of how defendants got to the wrong lane.
As defendants' counsel stated in conference, this is not "really a speed case. It's more a control of vehicle case." Id. 5.142. Thus, the theory is secondary, because as noted above, on the evidence in this case, negligence was established merely by showing that one driver was on the wrong side.
The tachograph evidence therefore had only tertiary significance. It reinforced plaintiffs' expert's independent reconstruction of defendants' speed.
Because the parties had at best a dim recollection of the accident, and because there were no eyewitnesses, each side called an expert to try to reconstruct the accident. Defendants' expert, Dr. Batterman, opined that the accident happened in defendants' lane. N.T. 4.182. His opinion was based on examination and photographs of the damaged vehicles and the accident scene, especially gouge marks in the road. Based on the same kind of information, plaintiff's expert, Dr. Treitterer, reached the opposite conclusion. Id. 3.140, 3.140-.154. Thus, the case boiled down to which expert the jury believed.
Because neither expert relied on the tachograph chart, its effect on the ultimate factual issue was, at most, insignificant. Thus, if admission of the tachograph evidence was error, it was harmless.
B. Exclusion of Evidence
Defendants also assign as error two refusals to permit questions and answers attempting to recall prior testimony. Defendants claim that it was erroneous to prevent their accident reconstruction expert from reading aloud six pages of plaintiff's deposition. Defendants' Memorandum of Law, at 2-3; see N.T. 4.178-.181. This was not error. First, Fed.R.Civ.Pro. 32(a)(4) precluded defendants from reading in only pages 20-26 (where plaintiff said the road was straight,) without also reading in page 37, (where plaintiff said the road curved slightly and was "practically straight to a professional driver"). See N.T. 4.220. It was within the court's discretion to insist that the deposition be as though the witness were then present and testifying. See Fed.R.Civ.Pro. 32(a); Fed.R.Evid. 611(a). Finally, I cannot understand how the ruling could have been prejudicial; defendant could have, but did not choose to, interrupt the expert's testimony in order to read in the deposition. N.T. 4.181. In any event, the six pages were admitted and read to the jury. Id. 4.214-.220.
Second, defendants claim that the court erroneously refused to permit questioning of defendants' expert concerning the percentage error in the tachograph recording of mileage.
Defendants' Memorandum of Law, at 3-4; see N.T. 4.141-.146. Objections to the questions were sustained because they attempted to recall testimony, id. 4.141-.142, .145. The court's eventual ruling, however, allowed defendants to pose assumptions "without stating or suggesting that those assumptions are founded in testimony." Id. 4.145. Defendants never did so. It was not error to require that questions be posed without introduction of hearsay in the form of attempted recollection of testimony of a non-party. Furthermore, even if erroneous, I cannot perceive, and defendants do not explain,
why such a restriction in the form of question was prejudicial.
C. Point for Charge
Defendant argues that the court erroneously refused their point for charge number four. Defendants' Memorandum of Law, at 4; see N.T. 5.146. This charge consisted of large portions of ICC regulations, 49 C.F.R. §§ 392.3, 395.2, 395.3 (1980); a statement that the evidence showed that plaintiff had violated the regulations and an instruction that if the jury found that violation of regulations was the proximate cause, the jury must find plaintiff negligent.
This instruction was refused. It usurped the jury's role as fact finder by stating that the evidence showed a violation. Also, it is not clear to me that the evidence would allow the jury to find that plaintiff had been "on duty" for fifteen hours. See 49 C.F.R. §§ 395.2(a), 395.3(a)(2). Furthermore, I viewed the subject matter of the regulation (limiting the number of hours a driver may be on duty) as more properly a matter for argument to the jury. N.T. 5.146. Defendants' contention, which they were permitted to argue, was that as a result of being on duty so long, plaintiff fell asleep at the wheel.
It was not error to refuse this instruction. Pennsylvania law does not support the contention that such a charge is mandatory. In the only case involving this instruction, Ridley v. Boyer, 426 Pa. 28, 31-32, 231 A.2d 307, 308-09 (1967), the Pennsylvania Supreme Court held merely that such a charge was not erroneous. Id. at 32, 231 A.2d at 309 ("The court was on the highway of proper instruction, when it spoke thus.") (Musmanno, J.). In any event, refusal was not prejudicial. Defendants were allowed to argue this issue to the jury as a matter of fact. Indeed, defendants were not precluded from introducing and explaining the regulation in the trial or thereafter, arguing the regulation to the jury.
Most important, the issue whether the regulations were violated is only tangentially related to the ultimate issue of where the accident occurred. See part II.A.3. supra.
D. Verdict Against Weight of Evidence
Finally, defendants argue that the verdict was against the weight of the evidence because plaintiffs' expert's reconstruction of the accident conflicted directly with plaintiff's version. I perceive no such conflict. For the reasons given in plaintiffs' memorandum, the expert's reconstruction of the accident is compatible with plaintiff's testimony.
For the above reasons, defendants' motion for a new trial must be denied.