The government is accused of blacklisting Muslims seeking U.S. citizenship by ACLU of Southern California says burdensome background checks put applications on hold for years.

Houston immigration attorney Gordon Quan argues one of his clients was denied because he attended a political rally 30 years ago.

“He was pro the U.S. against a group that was anti-U.S. and then got arrested,” Quan tells KTRH News.  “Now, because he's from Iran they think maybe he's a terrorist.”

The program in place since 2008 also kept another of Quan's clients – a local businessman – from becoming a citizen.

“He didn't put down that he was a member of his school PTA when they asked what organizations are you a member of,” he says.  “That's the kind of miniscule issues that I've seen.”

Supporters of the program argue these Muslims are not U.S. citizens yet, therefore they are not protected by the Constitution.

“People that come from countries that 90% of the terrorists are known to have come from, like Yemen and Saudi Arabia, then its our government's responsibility to vet those people more stringently,” says Eric Thompson who operates a social media site called Texans Against Sharia Law.

A spokesman for the U.S. Citizenship and Immigration Services says the country's safety and integrity of the system comes first.