release someone, or how prohibitively high they set bail. Some judges are very permissive. Others are strict. So imagine that one set of strict judges sees 1,000 defendants and releases 25 percent of them. Another set of permissive judges sees 1,000 defendants, who are in every way equivalent to the other 1,000, and releases 75 percent of them. By comparing the crime rates of the released defendants in each group, you can get a sense of how many harmless people the strict judges jailed, and how many dangerous people the permissive judges set free. That estimate, in turn, can be applied to the machine’s predictions. When it passes judgment on its own 1,000 defendants, how much better is it than the strict judges on the one hand, and the permissive judges on the other? This sounds highly complicated, and it is. But it’s a well-established methodology. For a more complete explanation, I encourage you to read Mullainathan’s paper.
Part Two
Default to Truth
Chapter Three
The Queen of Cuba
1.
Let’s take a look at another Cuban spy story.
In the early 1990s, thousands of Cubans began to flee the regime of Fidel Castro. They cobbled together crude boats—made of inner tubes and metal drums and wooden doors and any number of other stray parts—and set out on a desperate voyage across the ninety miles of the Florida Straits to the United States. By one estimate, as many as 24,000 people died attempting the journey. It was a human-rights disaster. In response, a group of Cuban emigrés in Miami founded Hermanos al Rescate—Brothers to the Rescue. They put together a makeshift air force of single-engine Cessna Skymasters and took to the skies over the Florida Straits, searching for refugees from the air and radioing their coordinates to the Coast Guard. Hermanos al Rescate saved thousands of lives. They became heroes.
As time passed, the emigrés grew more ambitious. They began flying into Cuban airspace, dropping leaflets on Havana urging the Cuban people to rise up against Castro’s regime. The Cuban government, already embarrassed by the flight of refugees, was outraged. Tensions rose, coming to a head on February 24, 1996. That afternoon three Hermanos al Rescate planes took off for the Florida Straits. As they neared the Cuban coastline, two Cuban Air Force MiG fighter jets shot two of the planes out of the sky, killing all four people aboard.
The response to the attack was immediate. The United Nations Security Council passed a resolution denouncing the Cuban government. A grave President Clinton held a press conference. The Cuban emigré population in Miami was furious. The two planes had been shot down in international airspace, making the incident tantamount to an act of war. The radio chatter among the Cuban pilots was released to the press:
“We hit him, cojones, we hit him.”
“We retired them, cojones.”
“We hit them.”
“Fuckers.”
“Mark the place where we retired them.”
“This one won’t fuck with us anymore.”
And then, after one of the MiGs zeroed in on the second Cessna:
“Homeland or death, you bastards.”
But in the midst of the controversy, the story suddenly shifted. A retired U.S. rear admiral named Eugene Carroll gave an interview to CNN. Carroll was an influential figure inside Washington. He had formerly served as the director of all U.S. armed forces in Europe, with 7,000 weapons at his disposal. Just before the Hermanos al Rescate shoot-down, Carroll said, he and a small group of military analysts had met with top Cuban officials.
CNN: Admiral, can you tell me what happened on your trip to Cuba, who you spoke with and what you were told?
Carroll: We were hosted by the Ministry of Defense. General Rosales del Toro.… We traveled around, inspected Cuban bases, Cuban schools, their partially completed nuclear power plant, and so on. In long discussions with General Rosales del Toro and his staff the question came up about these overflights from U.S. aircraft—not government aircraft, but private airplanes operating out of Miami. They asked us, “What would happen if we shot one of these down? We can, you know.”
Carroll interpreted that question from his Cuban hosts as a thinly veiled warning. The interview continued:
CNN: So when you returned, who did you relay this information to?
Carroll: As soon as we could make appointments, we discussed the situation…with members of the State Department and members of the Defense Intelligence Agency.
The Defense Intelligence Agency—the DIA—is the third arm of the foreign intelligence triumvirate in the U.S. government, along with the CIA and the National Security Agency. If Carroll had met with the State Department and the