Thursday Thinkpiece: Alarie and Green on Supreme Court Interventions

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Benjamin R.D. Alarie & Andrew J. Green,
(2010) 48 Osgoode Hall Law Journal 381
Excerpt pp. 408-410

[Footnotes omitted. They are available in the original via the linked title above.]


There appear to be several regularities that emerge from these analyses of the intervener data. From the indirect analysis, the lesson that emerges is that interveners have little or no effect on how judges sort themselves in policy space. That is, if interveners are shifting judges in a more conservative or more liberal direction, it appears that interveners are shifting the members of the Court as a bloc or, alternatively, not so far or so differentially as to cause judges to occupy a different ranking in policy space vis-à-vis his or her colleagues on the Court.

From the direct analysis, we learn that the presence of an intervener does have a modest effect in increasing the liberality of the decisions of the Court, even when one does not control for the type of intervener. Once controls are used for the identity of the intervener and the form of each intervention (liberal, conservative, or neutral), this effect is disaggregated into a moderate liberal boost of about 3 to 4 per cent for each liberal intervener, a more significant conservative boost of 4 to 6 per cent for each conservative intervener, and an equally significant liberal boost of about 4 to 6 per cent for each neutral intervener. Further, while it appears that some judges are more affected by certain types of interveners than other judges, the result from the indirect method that the members of the Court appear to be affected en masse is consistent with these results from the direct analysis.

We also learned that all judges are susceptible to intervener influence in a statistically significant way. Two measures of ideology appear to affect the liberality or conservatism of judicial voting. The first is the party of the appointing prime minister and the second is the judge’s estimated ideal point. Gender also matters. But a judge’s province of origin, the length of time a judge has been at the Court, or the nature of the judge’s legal career prior to joining the Court (i.e., academic, practitioner, appellate judge, et cetera) are all statistically insignificant.

What do these results tell us about our three stories of why the Court may allow interventions? First, the acceptance story would have required there to be no statistically significant relationship between the presence of interveners (or particular types of interveners) and the decision making of the Court or particular judges. The modest but significant impact of interveners on voting by the Court as a whole and by individual judges cuts against the acceptance story. There may be instances where particular parties are granted leave to appeal on acceptance grounds, but the evidence suggests that acceptance is not the sole determinant of a decision to grant leave to intervene.

Second, in terms of the accuracy story, the results from the individual judges indicate that in the presence of interveners judges in some cases vote in a direction different than would be predicted from general indicators of their ideology. The clearest example is that judges with high liberal voting percentages (such as Justices Arbour and Fish) tended to vote more conservatively in the presence of conservative interveners. Moreover, if the party of the appointing prime minister is taken as an indicator of ideology, liberal judges (judges appointed by Liberal prime ministers) vote more conservatively in the presence of conservative interveners and some conservative judges (such as Justice L’Heureux-Dubé, who was appointed by a Conservative prime minister) vote in a more liberal direction in the presence of a liberal intervener. The same results hold when the ideal point of the judge is used instead of the relatively crude “party of the appointing prime minister” measure of ideology.

Finally, we found little support for the affiliation story, particularly given the difficulties of separating it from the accuracy story. For example, there is clear evidence that conservative judges (judges with low liberal voting rates) vote conservatively in the presence of conservative interveners, but so too do liberal judges. It may be that they are all getting useful information from these interveners. As noted above, when the cross-judge characteristics were included rather than the judges themselves, the party of the appointing prime minister had a small, but statistically significant, impact on how judges voted. However, the key is how ideology impacts the way in which particular judge votes in the presence of a similarly inclined intervener. Our results indicate that liberal or conservative judges (as measured by the party of the appointing prime minister or by the judge’s ideal point score) are not particularly affected by interveners with similar policy inclinations.

The number of interveners before the Supreme Court of Canada has in- creased rapidly in recent years. On one view this increase could be concerning—it could indicate that judges of the Court are merely trying to justify or bolster their pre-existing policy inclinations by allowing submissions from interveners with similar views. Alternatively, the Court may be granting interventions to try to gain acceptance of its decisions by a larger community, but without any observable benefit in terms of the accuracy of the Court’s decisions. However, our results are consistent with a more optimistic story. The Court is allowing a higher number of intervening parties and appears to be using the interventions to better understand the impacts of its decisions. This optimistic story is similar to what Collins found in examining the impact of interveners in the United States. In contrast, however, far fewer appeals have interveners at the Supreme Court of Canada. This result may also be consistent with the optimistic story. The Court here is particularly willing to hear from interveners if there is a possibility of gaining some valuable information—and potential interveners understand this. For that reason, there may be a feedback effect on the willingness of would-be interveners to attempt to obtain leave to intervene. The increase in the number of interveners, so far at any rate, seems to be a positive development in the practice of the Court.

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