By Chris Strohm CongressDaily May 5, 2010

Senate Homeland Security and Governmental Affairs Committee Chairman Joe Lieberman, I-Conn., said Tuesday that he plans to introduce legislation in the coming days that would strip U.S. citizenship from Americans affiliated with a known terrorist organization.

Lieberman's announcement came in the wake of the arrest of Faisal Shahzad, a naturalized U.S. citizen who was born in Pakistan, for allegedly trying to set off a vehicle bomb in New York's Times Square.

But it also represents one of the first major legislative responses to concerns about U.S. citizens who become radicalized and motivated to carry out terrorist attacks. Besides Shahzad, other suspected American terrorists include Army Maj. Nidal Hasan, who has been charged with killing 32 people at Fort Hood, Texas, in November and David Headley, whom U.S. authorities recently arrested; he is accused of conspiring with Lashkar-e-Taiba to launch attacks in Mumbai, India, in 2008.

But the American Civil Liberties Union branded as "misguided" proposals that would strip citizenship from suspects who have not been convicted of any crime and other steps that deny suspects their right to due process.

"The Obama administration should reject all calls to circumvent the criminal justice system when handling terrorism suspects," said Laura Murphy, director of the ACLU Washington legislative office. "Obeying the Constitution is not optional, and we don't decide whether to apply it on a case by case basis."

Lieberman said his legislation would expand on current law.

"There's an existing law that says that if a citizen of the United States is a member of a military of foreign country with whom the U.S. is at war, they lose their citizenship. There's a process by which they can appeal it. So we wouldn't alter that process," he said.

"But what we would add to it is, in the unique circumstances of unconventional war, if there's evidence that an American citizen is affiliated with a foreign terrorist organization as designated by the State Department then they would lose their citizenship. Because it just seems to me if you basically declare yourself to be an enemy of the United States you're no longer entitled to the rights of citizenship."

Senate Homeland Security and Governmental Affairs Committee ranking member Susan Collins, R-Maine, called Lieberman's proposal "a very intriguing idea" but emphasized she had not examined it in detail.

Collins said she hopes the Times Square incident will compel lawmakers to approve legislation she wrote last year with Lieberman that would give people legal protections from lawsuits if they report what they believe is terrorist activity in public places.

"It's to give protection to people like that alert street vendor who reported suspicious activity," she said, referring to the man who alerted police to the smoking, bomb-laden vehicle Shahzad allegedly abandoned on the street. "So it's intended to protect the see-something, say-something approach since this case clearly illustrates that alert citizens who are willing to report indications of suspicious activity are our best line of defense."

Collins said the bill would not protect people who deliberately make false statements to police.

Although Congress did not approve the bill last year, a section of it was enacted in December to provide immunity from civil liability to people who report "suspicious terrorist activity" on transportation systems.

Meanwhile, the Shahzad case has renewed debate in Congress on whether terrorism suspects should be read their Miranda rights.

Attorney General Eric Holder said Tuesday that Shahzad was not immediately read his rights and gave up valuable information. Shahzad later was given his Miranda rights and continued to cooperate and provide information, Holder said.

"If you give the Miranda rights reading and he decides to stand on that, then you are blocked," said Senate Minority Whip Jon Kyl, R-Ariz.

"Now maybe we got lucky and he said, 'I'll go ahead and talk to you anyway,' but you didn't know that when you read the rights to him," Kyl said.

"It is better in these kinds of cases to get the intelligence first and then, if you decide you want to proceed with an Article III [criminal court] prosecution, then read the Miranda rights," he added.

Humberto Sanchez contributed to this report.