MIAMI — It may be getting harder to sneak into the United States, but once you’ve arrived, getting fake documents in Florida is a piece of cake.

Counterfeit, altered or stolen birth certificates coming from Puerto Rico are the Holy Grail to Florida’s undocumented. With a phony birth certificate you can live the American dream. You can also enroll in school, land a job and get a driver’s license. (It has also been estimated that up to 40 percent of the passport fraud in the United States involves counterfeit or stolen birth certificates from Puerto Rico.)

The racket was made possible thanks to a law passed in 1917 by Congress, which granted U.S. citizenship to all Puerto Ricans. Now, desperate economic times together with eye-popping profits have created a black market where for as little as $25 a birth certificate can be bought and later resold for $5,000.