The American Civil Liberties Union of Southern California said in a report that the criteria used by US Citizenship and Immigration Services to blacklist immigrants are overly broad and include traveling through regions where there is terrorist activity.
The report says immigration officers are instructed to find ways to deny applications who have been deemed a national security concern. For example, they'll claim they failed to receive sufficient information from the immigrant.
"It is essentially creating this secret criteria for obtaining naturalisation and immigration benefits that has never been disclosed to the public and Congress hasn't approved," said Jennie Pasquarella, an ACLU staff attorney and the report's author.
"I feel like ultimately this is just about politics. They don't want to be seen as having granted citizenship to somebody who's going to be the next Boston bomber," she said.
It was not immediately clear how many immigrants have been reviewed under the programme, which began in 2008 and is formally known as the Controlled Application Review and Resolution Programme.
Asgari is still waiting for a decision on his naturalisation application, the ACLU said.
Christopher Bentley, a spokesman for Citizenship and Immigration Services, said the agency routinely checks the background of immigrants applying for benefits and puts the country's safety, and the integrity of the immigration system, first.
"We are vigilant in executing these responsibilities, and will not sacrifice national security or public safety in the interest of expediting the review of benefit applications," Bentley said in a statement.
