Do Bigger Teams Win More Cases?

In prior posts, we have shared a number of insights from our Data-Driven Decisions program. Our work focuses on understanding how courts decide cases by identifying the factors associated with success or failure in litigation. That analysis serves an obvious predictive function: it helps estimate the likelihood that a court will decide a case in a particular way.

But prediction is only half the story. The more interesting question, from a practitioner’s perspective, is whether the data point to decisions we can actually control. Are there strategic choices that we as lawyers make that systematically increase (or decrease) the odds of success? We explore those questions in a series of posts over the coming months.

The first question we address: when it comes to litigation, are bigger teams better? More precisely, holding other factors constant, are larger legal teams associated with a higher likelihood of success?

The Dataset

Our Supreme Court of Canada leave database provides a useful testing ground for this question. There are three reasons for this:

1. It is a large dataset that contains thousands of decisions.
2. It is a consistent dataset, in that the court is always making the same kind of decision.
3. It is a rich set of variables known to correlate with whether leave is granted; in prior work, we have shown that many of these variables are robust predictors of outcome.

For present purposes, we looked at a particular field we had in our dataset: the number of lawyers acting for the applicants on a leave application. This information is publicly available on the Supreme Court’s website.

A few clarifications on how we structured the data:

• We relied on publicly available information on the Supreme Court’s website. The total number of lawyers listed on a leave application may be different than the total number of lawyers who worked on a leave application, though it seems likely the two are strongly correlated.
• We counted the total number of counsel acting for all applicants bringing leave applications, whether they represent a single party or multiple aligned parties. Our data do not distinguish between, for example, two applicants each represented by two lawyers and one applicant represented by four lawyers.
• We excluded cases in which both sides of a case sought leave to appeal (including both competing leave applications as well as conditional applications for leave to cross-appeal), as such cases might be associated with a larger team size of applicants while also having a higher likelihood of leave being granted for independent reasons.

Using that data, we analyzed the relationship between team size and the probability of obtaining leave.

The Results

The relationship between applicant team size and the likelihood of leave being granted is striking: as team size increases, so too does the likelihood that leave will be granted.

Self-represented litigants have, in practical terms, almost no chance of success. A single lawyer acting alone performs somewhat better, but still below average. From there, each additional lawyer is associated with a meaningful increase in the probability of obtaining leave. By the time an applicant has a team of four lawyers, the likelihood of success is materially higher than the baseline.

On its face, the data suggest a clear conclusion: larger teams are associated with better outcomes.

Correlation Doesn’t Mean Causation, But Strong Indicators Exist

What do these results actually mean?

One possibility is that larger teams causally lead to an increased likelihood of getting leave. Larger teams may produce better work.

An alternative but similarly causal explanation is that larger teams may be a form of signaling to the Supreme Court. A larger team may be an indicator to the court that a particular case is important, leading the court to be more likely to grant leave.

But the analysis of the data set out above does not uniquely lead to those explanations, and there are also plausible explanations with an opposite causal direction. For example, it may be that the cases most likely to obtain leave are the very cases that attract larger teams in the first place. Important constitutional cases, for example, are both more likely to be granted leave and more likely to involve multiple counsel. Similarly, clients’ high-stakes cases may be staffed more heavily from the outset. In that scenario, team size is not causing better outcomes; it is simply a proxy for underlying case quality or importance.

Understanding which way causality flows is important to practitioners. If larger teams lead to an increased likelihood of leave being granted, clients’ chances may be improved by adding team members. But if there is no causal relationship, adding new team members may increase cost to the client with no associated benefit. Distinguishing between those possibilities matters.

To untangle these possibilities, we evaluated whether the relationship between team size and success persists when controlling for other relevant factors. Our analysis showed that it did.

As one example, we limited the set to only private law cases where the Court of Appeal below unanimously dismissed the appeal. These are cases that our previous work suggested had a much lower likelihood of getting leave to appeal. While the probability of getting leave was lower, the relationship remained constant: larger team sizes were associated with a greater likelihood of leave being granted.

More generally, our work suggested that the positive association between larger teams and higher success rates remains even after controlling for:

• The type of case (including whether it raises constitutional issues)
• Characteristics of the Court of Appeal decision that correlate with case importance
• Other objective indicators of case importance captured in our dataset

That does not prove causation, but it is evidence consistent with a causal impact. The persistence of the relationship across controls makes a purely incidental explanation less persuasive.

The Takeaway: How Generalizable Are These Results?

Our analysis suggests that larger team sizes may lead to an increased likelihood of success for applicants in getting leave to the Supreme Court of Canada. The data do not tell us why larger teams are associated with better outcomes, but there are several plausible mechanisms:

• More rigorous testing of ideas
• More thorough research
• Sharper issue framing
• More polished written advocacy

In short, adding lawyers to a team may directly improve the quality of the leave application and therefore increase the chances of success.

Assuming that is correct, the next question is the extent to which this can be generalized to other litigation contexts. Without data in those other contexts, it is difficult to say with certainty. But our intuition is that it is reasonable to expect the same conclusion would apply in similar contexts, meaning complex and challenging cases.

Applications for leave to appeal to the Supreme Court of Canada are difficult: the odds are long, and a compelling leave application requires demonstrating the particular importance of your case as a matter of law against a broader legal backdrop. In the context of that kind of case, it seems plausible that adding resources and opposing views might be associated with a broader chance of success. We expect a similar dynamic in other high-complexity cases. By contrast, routine or simple cases offer less of an obvious explanation as to how larger teams improve odds of success. But at least in complex cases, bigger teams may be better.

At a minimum, the data suggest team size is a strategic variable worth considering deliberately, rather than treating staffing as purely a function of availability or cost.

That is exactly the kind of insight data can provide: not just what courts do, but what we can do differently in response.