How the “But For” Test for Causation in Law can be Adapted to Political Science

For social science, as for law, the concept of “causation” can  take on different forms. These forms of causation are “outside   the box” of the old Newtonian concept of causation. That is, a   one-on-one collision. For example, the “8 ball” in a pool game moved to the corner pocket because the cue ball struck it at the intended angle. The cue ball did that because Minnesota Fats hit the cue ball just right with his pool stick.

This is a mechanistic model of causation. In that model, the list of causes prior to Minnesota Fats could go back endlessly; or at least to the Big Bang of 13.8 billion years ago, which, mechanistically, is thought to be the First Cause of everything.

However, for the most part, social science, like law, envisions human behavior as conduct for which the actors are responsible. This need not be a “moral” responsibility, for which moral blame is attached. Instead, “causal responsibility” is simply a matter-of-fact, or practical, conception.

Voters, for example, go to the polls and vote because they feel a sense of civic duty; or because they want their candidate, or proposition, to win; or because they want to oppose a particular candidate or proposition. They are “agents.” That is, they can act with sufficient independence from mechanical causation to make them responsible for their actions as a matter of fact. The actions of voters set in motion a particular series of events. For example, candidate A is elected rather than B, C, or D. The newly elected official’s policies are enacted resulting in major changes in a society, such as laws permitting abortions without legal restrictions, or the forgiveness of all student loan debts, and making all higher education free. Elections have consequences, and the majority of voters who elected A share in the responsibility for what she does in office. Those voters share in the responsibility for the resulting chain of events that probably would not have happened “but for” their vote. Each voter for A is, in small degree, a “responsible cause” for the events that followed A’s election.

 In a non-mechanistic sense, those voters can also be said to be a secondary “cause” of official A’s actions in office. Of course, they are not the direct cause of her actions. She is the direct cause of what she does; that is, as an agent, she is first in responsibility for what she chooses to do in office.  But the voters have a secondary responsibility for having elected her.

“Responsible cause,” then, is a very different theory of causation than is the theory of cause as strictly mechanical. “Responsibility” implies choice, and the Newtonian mechanical theory of causation implies no choice, just mechanics.

Generally, the responsible cause, or causes, for a given event can be determined by applying the “But For Rule.” For example, suppose that while Governor of state P, Ms. A, through pressure and persuasion, moved the state legislature to pass a law de-criminalizing sex work. Suddenly, prostitutes began appearing in places where they had not been seen before, such as in the downtown office district, and in front of auditoriums where high school basketball games were held. Neither A nor the legislature put the sex workers there. However, they share some responsibility for that event. “But For” their prior actions, those places would have been off limits to the sex workers, and the police would make sure of that by immediately arresting them on sight.

Another way to shed light on the responsibility of A and the legislature, is to argue that they “set the stage” for the scandalous behavior of the street walkers. Here again, “But For” the prior actions of those officials, the sidewalks in the office district and in front of the stadium would have remained pristine. Those officials were not the “direct” cause of the event. They did not, for example, escort the street walkers arm-in-arm to those public places. However, when those officials de-criminalized sex work, they set the stage for the events that followed. They made it possible for the event to occur.

In social science, as in law, attributions of causation can be disputed. One way to resolve such a dispute is to ask whether a “reasonable person” would agree with the attribution of cause to some prior event, or disagree with it. In law, a jury is often called upon to consider that question. If a sufficient number of jurors agree, then causation has been established.

In social science, when a social scientist puts forth an attribution of causation, the question would be “would reasonable peers of this social scientist agree with this attribution of causation, or disagree?” Perhaps, for instance, the majority of peers disagreed on the grounds that no cause had been shown, but only a correlation of events.

However, if a sufficient number of peers agree, through journal articles or other professional communications, then that theory of causation may be said to be, at least tentatively, validated. Thus, this Post is setting forth a theory of causation which awaits the expected validation.

PS

1) Are you interested in seeing how the “but for” test of causation, taken from American jurisprudence, can be used in political science? Check out my paper on the APSA Preprint website, "How One Law in California, 'Costa-Hawkins,' Produces more Homeless than can be Helped, and has other Significant Unintended Consequences" at,

https://preprints.apsanet.org/engage/apsa/article-details/66cfbebd20ac769e5f27a777

2) The legal theory of causation is usually discussed in law books on Torts, particularly negligence. That’s where conduct causing harms is the focus. Any law book for the past 30 years entitled Prosser on Torts, or a more recent edition, called Prosser and Keeton on Torts, will have a section on causation. Of course, for political science the conduct will be government action and policies causing harms.

William J. Kelleher, Ph.D.

The Political Science Interpretivist

@InterpretivePo1