DEFENCE CHALLENGES PROSECUTION USE OF FORENSIC GAIT ANALYSIS AS EVIDENCE IN A MURDER TRIAL

R v Crupi (Ruling No 1) [2020] VSC 654 (7 October 2020)    

This case involves the accused who is charged with murder where the prosecution introduces a Forensic Gait Analysis (FGA) as evidence to prove that the accused is the shooter of the victim.  

Facts:  

Vincenzo Crupi (D) is charged with the murder of Joseph Acquaro (V). V was fatally shot at close range near his Brunswick East restaurant, the Gelo Bar. The prosecution (P) allege that D was the shooter.  

P submitted that the relevant “fact in issue” is the identity of the shooter and that the FGA evidence of Professor Pandy’s bears upon that issue. P relied on the following aspects of Professor Pandy’s evidence in support of its case that D was the shooter: his measurements and comparison of the spatio-temporal gait features of the subjects of the CCTV footage, namely, their step length, step frequency and walking speed; his opinion that the spatio-temporal features of the subjects’ gait are more consistent with the gait of an older person.

P submitted that Professor Pandy’s evidence is relevant because it rationally increases the probabilities that D was the shooter. P highlighted Professor Pandy’s finding that the mean step lengths of the subjects in the two groups of clips were ‘remarkably similar’. He also said the mean step lengths were ‘almost exactly the same’  

Issue: Is the FGA submitted by the prosecution admissible as evidence?  

Law:  

• S55 of Evidence Act 2008- Relevant Evidence  

1. The evidence that is relevant in a proceeding is evidence that, if it were accepted, could rationally affect (directly or indirectly) the assessment of the probability of the existence of a fact in issue in the proceeding  

Analysis:  

The general rule when assessing relevance is that one assumes that the impugned evidence will be accepted by the jury, unless no reasonable jury could accept it. Hence, one assumes the accuracy of Professor Pandy’s calculations, unless no reasonable jury could accept them.  

What factors may have affected the reliability of Professor Pandy’s calculations? He acknowledged that he sometimes rounded-off the number of steps taken between point A and point B in a given clip but he did not keep a record of when he did so. When asked about the number of times he did this, he first said ‘infrequently’, then he said ‘no more than 20% of the time’ which strikes one as a significant number of occasions. If those occasions were spread across both groups, they may have evened themselves out, so to speak, but Professor Pandy did not say positively that was the case. On the evidence, one cannot exclude the possibility that the rounding-offs were concentrated in one group. Professor Pandy said he sometimes had to make a subjective judgment as to the number of steps taken by the subject between points A and B. He acknowledged that the CCTV frame rates, about which he said he knew nothing, may have affected the accuracy of those subjective judgments. Professor Pandy used the time stamps on the CCTV clip to make his calculations but he did not check the accuracy of the various time stamps for the various CCTV cameras. Professor Pandy also acknowledged that the subjects did not always walk in a straight line between points A and B: at times, Professor Pandy noted excessive lateral movement by the subjects.  

It may well be, as P submitted, that none of these matters significantly affected the accuracy of Professor Pandy’s calculations but, on the present state of the evidence, there is no way of knowing whether that is the case. If the jury is to act rationally, there must be a proper basis for the jury to conclude that the accuracy of his calculations were not significantly affected by these matters. The evidence fails to provide a proper basis for such a conclusion.   

Conclusion: For failure to pass the test of relevance, the evidence is hereby inadmissible.

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