This Day in Philosophy — 23 August: the execution of Sacco and Vanzetti, the birth of Kenneth Arrow

The twenty-third of August gathers into one date two events that press on the idea of justice from opposite sides.

1927: Charlestown State Prison#

The Italian-born anarchists Nicola Sacco and Bartolomeo Vanzetti were put to death in the electric chair at Charlestown State Prison in Massachusetts shortly after midnight on 23 August 1927. The charge was murder.

The case was tried at the height of American hostility towards radicals. To many observers the proceedings had turned improperly into a spectacle; the prosecution could not produce the stolen money, and a substantial part of the evidence against the two men was later discredited.

The executions provoked demonstrations around the world. A broad circle that included Einstein, Dos Passos and Anatole France campaigned on the men's behalf.

The philosophical question: what does a fair trial secure?#

The Sacco-Vanzetti case is invoked again and again in the philosophy of law, because the difficulty it raises is not technical but a matter of principle.

Can a trial be unfair even where the rules of procedure have been formally observed?

The tradition that defends the rule of law holds that procedure is itself the guarantee: if the rules have been followed, the outcome is legitimate. The contrary view points out that procedure can be shaped from the outset by prejudice against one of the parties. The rule stays the same, but who ends up in the dock, which evidence is taken seriously and which witness is believed all change.

The argument continues today. Is the right to a fair trial a purely procedural guarantee, or a claim about the outcome as well?

In 1977, on the fiftieth anniversary of the executions, Governor Michael Dukakis of Massachusetts issued a proclamation acknowledging that Sacco and Vanzetti had been wronged in the conduct of their trial. The proclamation did not declare them innocent; it found that the trial had not been fair. The distinction shows the character of the argument rather well.

1921: Kenneth Arrow#

On the same date in 1921, Kenneth Joseph Arrow was born in New York. An economist, mathematician and political theorist, he was awarded the Nobel Prize in economics in 1972 and died in 2017.

Arrow matters to philosophy because of the doctoral work he published in 1951: the impossibility theorem.

Is collective choice possible?#

The question looks simple enough. How are we to convert the preferences of the individuals in a society into a coherent social preference?

Arrow argues that we ought to ask a few reasonable things of that conversion. For instance: if everyone prefers A to B, society should prefer A to B. Society's ranking of A against B should not change with the presence of some irrelevant option C. And the decision should not reduce to the preferences of a single person.

What the theorem shows is this: where there are more than two options, no rule of social preference satisfies all of these reasonable conditions at once.

This is not a problem about vote-counting technique; whichever method you choose, one of the conditions falls away.

Its effect on democratic theory#

The first reading of the result is bleak: there is no coherent thing called the will of the people, and majority decisions vary with the procedure used.

But the argument did not stop there. Amartya Sen showed that some of Arrow's conditions could be relaxed; the picture altered in particular if individual levels of welfare were taken to be comparable. Sen's line later opened onto the capabilities approach and the ethics of development.

John Rawls took the problem from another direction: the criterion of justice is not the aggregation of existing preferences but the principles the parties would agree upon without knowing their own positions.

Read together, the two events yield this: justice can be secured neither by correct procedure alone nor by correct addition alone. The twentieth century learned the lesson twice over, by two different routes.