Section 548 of the Code directs the justice or judge at the preliminary inquiry to commit the accused for trial on any indictable offence if the evidence in support of that charge is sufficient. It also requires that the accused be discharged in respect of any charge on which the evidence is not sufficient. Everything turns, therefore, on what is meant by "sufficient" evidence. The courts have provided a test that has been consistently applied for many years but, as will be seen, remains uncertain in some important aspects.
In Shephard, the Supreme Court stated that the test of sufficiency at the preliminary inquiry, as for a directed verdict and for committal in extradition matters, is whether a reasonable jury, properly instructed, could find the charge proved beyond reasonable doubt.80The core of uncertainty in this test lies in the degree to which an assessment of the evidence permits or requires the presiding judge to consider the proba-
tive force of the evidence. It is arguable that a reference to whether the jury could return a finding of guilt is at least some indication that the presiding judge should assess the force of the evidence.
A convenient fashion in which to examine the test of sufficiency is to look at the criteria of completeness and weight. The first of these means only that the prosecution leads evidence corresponding to each of the elements of the offence as defined in the substantive criminal law, including identification.81In a case of assault, for example, this would mean that there was evidence led that the accused intentionally applied force to another person without that person’s consent. In the general run of cases, the criterion of completeness poses few difficulties.
It is the criterion of weight that is problematic. The Supreme Court and other courts have said repeatedly that it is not the function of the judge to assess the weight of evidence at the preliminary inquiry.82Accordingly, a judge must not assess the credibility of witnesses who testify.83This has led some to assert that if there is any evidence on all essential elements in the charge there should be an order of committal.84
The reason most commonly invoked for this assertion is that the justice or judge at the preliminary inquiry must not usurp the functions of the jury or judge at trial in determining the strength of the case.85
On the other hand, if the prosecution evidence is such that no reasonable jury, properly instructed, could find the charge to be proven beyond a reasonable doubt, this seems like a relevant consideration. Whether she is entitled to assess the credibility of witnesses or not, one might argue that the judge should discharge the accused if no reasonable trier of fact could find the accused guilty on the evidence adduced by the prosecution. To reach such a conclusion would not be to usurp the role of the ultimate trier of fact.
The resolution of this problem depends upon the perceived purpose of having preliminary inquiries...