A federal appellate court has ruled in the city’s favor against a lawsuit challenging the police sweeps during Mayor Giuliani’s tenure that led to the arrest of homeless people who were caught sleeping on streets and in parks.

In a split decision released Thursday, a three-judge panel of the 2nd U.S. Circuit Court of Appeals upheld the arrest nine years ago of a homeless Army veteran, Augustine Betancourt, who spent a night on a park bench, sheltered by three cardboard boxes.

The court ruled that a city law criminalizing the erection of “any shed, building, or other obstruction” on public property did apply to Mr. Betancourt’s construction of cardboard bedding.

“We think it clear,” the decision stated, that the law “was meant to forbid any obstruction, whether permanent or temporary.”

But Mr. Betancourt’s claim that the law was too vague to be applied against him and other homeless people received a sympathetic hearing from Judge Guido Calabresi, who wrote a dissenting opinion.

The law in question, Judge Calabresi wrote, “is an impenetrable law that could be read to allow police officers to apply the ordinance almost however they want against virtually whomever they choose. And on the night of February 27, 1997, that is precisely what they did as part of the mayor’s “‘Quality of Life’ campaign against the homeless.”

Mr. Betancourt’s appeal of a lower court’s decision upholding his arrest was delayed as he pursued a claim that he was wrongfully strip-searched during his detainment. He settled that claim with the city for $15,000. Mr. Betancourt is no longer homeless and lives in a single-occupancy dwelling, his attorney, Douglas Lasdon, said. Mr. Lasdon added that the whereabouts of a second plaintiff in the lawsuit, also a homeless man, were unknown.