Latinos made up a disproportionate number of the people arrested who were not the stated targets of the raids, and many of their arrest reports gave no basis for why they were initially seized, said the report, which was based on data from raids in New York and New Jersey.
The Immigration Justice Clinic at Yeshiva University's Benjamin N. Cardozo School of Law analyzed home raid arrest records from Immigration and Customs Enforcement offices in Long Island and throughout New Jersey. The clinic, founded last year, represents indigent immigrants facing deportation.
Its report, released Wednesday, said that since ICE agents use administrative warrants - instead of judicial warrants, which give law enforcement unfettered access - they must have a resident's consent to enter a home or else violate the constitutional right to protection against unreasonable searches.
On Long Island, 86 percent of arrest records from 100 raids between January 2006 and April 2008 showed no record of consent being given, the report found. In northern and central New Jersey, no record of consent being given was found for 24 percent of about 600 arrests in 2006 and 2007, it found.
Peter Markowitz, director of the clinic and one of the authors of the report, said raids often are carried out with great force, with immigration officials pushing their way into homes in pre-dawn or late-night hours.
The raids are ostensibly aimed at targeted individuals who present threats either to national security or community safety, but arrests of illegal immigrants nearby, known as collateral arrests, are also made.
While the report only analyzed data from two states, it said the pattern suggested the problem was nationwide. It listed examples from California, Texas, Arizona, Massachusetts, Georgia and other places.
A federal judge in Connecticut last month ruled that federal agentsof four illegal immigrants in a 2007 raid under similar issues. The judge ruled the immigration agents went into the immigrants' homes without warrants, probable cause or their consent, and he put a stop to deportation proceedings against the four defendants.
"The widespread illegality by a law enforcement agency should be kind of shocking to anybody," Markowitz said.
In a statement, ICE said its agents uphold the country's laws.
"We do so professionally, humanely and with an acute awareness regarding the impact enforcement has on the individuals we encounter," it said.
The agency said it also had a mandate to pursue all illegal immigrants, whether targeted or not. A spokesman for the agency declined to comment further.
The agency has about 100 Fugitive Operations Teams around the country; in fiscal year 2008, the teams made more than 34,000 arrests.
The report also found that Latinos were a disproportionate number of collateral arrests. In both New Jersey and on Long Island, two-thirds of the targeted detainees were Latino. But 87 percent of collateral arrests in New Jersey were Latino, as were 94 percent of the collateral arrests in Long Island.
Collateral arrest records can indicate why the person was seized and questioned. But the report found that almost all the records that didn't contain that information were for Latinos taken into custody. The report said that supported community complaints that Latinos were targeted for arrest simply because of how they looked or how well they spoke English.
The report makes several recommendations, including limiting the use of home raids to a last resort for targets who pose a serious risk to national security or have violent criminal records; the use of judicial rather than administrative warrants, and the videotaping of all home raids.
It also calls for the Department of Homeland Security Office of the Inspector General to conduct an investigation.
"These are violations that go to the very heart of the Constitutional expectation of privacy in this country," Markowitz said.