DENVER (AP) The Colorado Supreme Court is hearing arguments Thursday about the legality of an identity theft investigation that targeted hundreds of suspected illegal immigrants who filed U.S. tax returns without valid Social Security numbers.
A District Court judge halted the investigation in April. He ruled Weld County authorities violated people's privacy rights and had no probable cause to inspect the tax returns, which were used to file charges of criminal impersonation and identity theft against more than 70 people.
Weld County appealed the decision.
Authorities say that as many as 1,300 suspected illegal immigrants were using other people's identities to work and to file taxes. Some of those charged face deportation. Others pleaded guilty before the court stopped the investigation.
Weld County seized the returns last year from a tax preparation firm that catered to Latinos in Greeley, where Hispanics make up about a third of the population. The investigation was stopped just as authorities prepared to charge more people.
Prosecutors in other states have expressed interest in Weld County's use of tax documents to go after illegal immigrants. Immigrant advocacy groups have said Weld County is the only jurisdiction to use tax records which are confidential under federal law to prosecute illegal immigrants.
Weld County District Attorney Ken Buck, a Republican U.S. Senate candidate who advocates stricter immigration laws, has maintained the investigation was about identity theft, not illegal immigration.
Dubbed "Operation Numbers Game," the probe began after a Texas man told Greeley authorities someone there was using his identity. The suspect in that case alerted law enforcement to the firm that prepared his taxes. Investigators obtained a search warrant to seize thousands of tax documents.
Weld County is appealing the lower court's ruling that there was no probable cause for the search warrant. The District Court judge called the warrant "nothing more than an exploratory search based upon suspicion that some unknown person or persons" committed a crime.
The county is appealing another judge's ruling that barred prosecutors from filing more cases using evidence seized from the tax preparer.
Filing taxes is mandatory for anyone who earns income in the U.S. regardless of legal status. Many of the people targeted in Operation Numbers Game were filing taxes with government-issued taxpayer identification numbers.