Twenty-one Cuban migrants made it 84 miles in their rickety boat, but it was perhaps not quite far enough.

Currently, the group is in legal limbo, in the custody of the United States Coast Guard, on a ship somewhere in the Caribbean.

In downtown Miami, a federal judge will soon decide whether the U.S.’s Cuba-specific immigration policy – known colloquially as "wet foot, dry foot" – applies to the 21.

Ramon Saul Sanchez filed the federal lawsuit Tuesday afternoon on the refugees’ behalf.

"To get to freedom, and then when you're about to get to freedom, somebody picks you up from the water and says your feet are wet, you go back. That's very sad,” he said.

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The big question for the judge is whether a historic, 109-foot-tall lighthouse is on American soil or not. The lighthouse, called “American Shoal,” sits 6 miles south of Sugarloaf Key, not far from Key West, Florida.

The Coast Guard found the migrant group hanging onto the lighthouse Friday. The water there is 10 feet deep and the lighthouse is not actually on a rock but stands on an octagonal platform. It’s maintained by the United States and was once depicted on a postage stamp.

By the time the Coast Guard got to the Cubans, they had been on the lighthouse for hours, so — technically, at least — their feet were dry.

The federal judge must now determine whether this counts as part of the U.S. mainland or not. If it does, the Cubans get to stay in the U.S. If not, they’ll be sent back to the communist island.

Unlike illegal migrants from all other countries, thanks to the Cuban Adjustment Act, people from that country are automatically deemed to be political refugees and get permanent green cards after one year. They also receive generous, taxpayer-subsidized welfare benefits like Social Security insurance, which is one of the driving forces for the Cuban migration.

The other is a current fear on the island that wet foot, dry foot may not have much time left – meaning, if you’re Cuban and willing to make the perilous 90-mile journey to Florida in a boat (recent trips have taken a dozen days out at sea), you had better do it now.

And they may be right about that. Support for the policy is eroding in Congress.

"America is getting fleeced by people who are claiming to be refugees and are just taking advantage of our welfare system and our generous immigration law,” says South Florida Republican Congressman Carlos Curbelo, who happens to be a Cuban-American and the sponsor of the House bill to do rescind wet foot, dry foot. In fact, all the Cuban-Americans in Florida’s Congressional delegation agree with Curbelo.

Republican Senator Marco Rubio is sponsoring the Senate's version of the bill.

“By some estimates, this is costing the American taxpayer $400 to $500 million a year,” said Rubio. “And we now have growing evidence of people that come to the United States, claim to be Cuban refugees and then are traveling back and living in Cuba while receiving federal benefits and their family's wiring them the money."

It seems obvious, but now a nonpartisan report confirms it: Ending automatic welfare payments to Cuban immigrants would save the federal government money.

The non-partisan Congressional Budget Office estimated that the U.S. government would save $2.45 billion over 10 years if going forward Cubans were not classified automatically as refugees and, by extension, eligible for benefits such as food stamps. The agency estimated that some $1 billion would be saved from 2017-21, and an additional $1.4 billion from 2022-27, according to The Miami Herald.

The flow of Cuban migrants has been surging since presidents Barack Obama and Raúl Castro began normalizing relations at the end of 2014.

Coast Guard interdictions of Cuban boaters and rafters in the Florida Straits are on pace to exceed 3,000 this year. Six years ago, that number was about 400.