Novel Scientific Evidence of Intoxication: Acoustic Analysis of Voice Recordings from the Exxon Valdez

Abstract

On March 24, 1989, the oil tanker Exxon Valdez ran aground in Prince William Sound, causing the worst accidental oil spill in history. Captain Joseph J. Hazelwood was in command of the ship, although he was not on the bridge at the time of the accident. Almost immediately, rumors and allegations surfaced suggesting that Hazelwood was intoxicated, but no hard evidence came to light. A captain at sea is a long way from the nearest police officer with a breathalyzer. Hazelwood denied having been intoxicated, and an Alaska jury acquitted him of the charge. There seems to be no way to prove whether or not Hazelwood really had been drinking. Or is there? Recent work in the Speech Research Laboratory at Indiana University’s Psychology Department suggests that intoxication can be detected by acoustic-phonetic analyses of a suspect’s voice.1 The National Transportation Safety Board (NTSB), the federal agency charged with investigating the Exxon Valdez accident, made available to the authors copies of tape recordings of conversations which took place between Captain Hazelwood and the Coast Guard from before, during, and after the accident.2 Analyses of these tapes suggest that Hazelwood was indeed intoxicated when his ship ran aground.3 This novel application of speech science techniques for measuring the effects of alcohol on speech has never, to the knowledge of the authors, been attempted in a civil or criminal case. Our analyses raise several obvious questions: Are the results reliable? How certain can we be that Captain Hazelwood was intoxicated? And, if this new testing procedure, based on voice recordings, can indeed determine that someone was under the influence of alcohol, are the results admissible in court? The answers to these questions have implications beyond their obvious application to determining fault in the more than three hundred pending lawsuits concerning the Alaska oil spill.4 In many cases, defendants may be far away from the nearest breathalyzer or may refuse to submit to blood-alcohol tests. In the absence of reliable, objective evidence of whether a defendant had been drinking, courts must rely on a presumption of guilt based on a defendant’s refusal to take a test,5 admit the speculative opinions of witnesses, or let the jury guess after listening to tape recordings.6 If a new measurement procedure exists that can, at least in some cases, provide objective indications of a person’s physical state or condition, then courts could more reliably convict the guilty and acquit the innocent in cases where no chemical blood test results exist. In this article, we describe this new testing procedure, using the analyses performed on Captain Hazelwood’s voice as an example. We then discuss whether the results should be admissible under the rules governing novel scientific evidence. We conclude that the kinds of acoustic-phonetic analyses described in this article produce reliable and relevant evidence that should be admitted when supported by proper expert testimony. We do not claim that speech analyses conclusively prove that Captain Hazelwood was intoxicated when the Exxon Valdez ran aground. Rather, we believe that the analyses of Hazelwood’s voice produce data consistent with intoxication. They therefore should be admitted into evidence and considered by the jury along with other relevant information.