An extradition treaty between the United States and Hong Kong, signed in 1996, could determine if and how alleged NSA leaker Edward Snowden is handed over to American authorities and brought back to the U.S. to face any charges.
The process could take months or years.
The treaty governs the transfer of suspected criminals between the U.S. and Hong Kong, which have a well-established record of bilateral cooperation.
Rep. Peter King, R-N.Y., late Sunday became one of the first U.S. officials to call for "extradition proceedings at the earliest date" and warned that "no country should be granting this individual asylum."
Other top lawmakers have also called for an aggressive prosecution.
For an extradition case to proceed, however, the U.S. first must decide to press charges and present probable cause to Hong Kong authorities. The alleged offense must also meet the treaty's test of "dual criminality," meaning it is a crime punishable by imprisonment of more than one year in both countries. (Hong Kong presumably has a law similar to the U.S. Espionage Act, for example.)
Local officials could arrest and hold Snowden for 60 days pending a formal extradition request from the State Department, according to the treaty. Once the formal request is received, a Hong Kong city court and local leaders would then determine whether to comply.
There appear to be at least two possible grounds on which they could refuse:
(1) Beijing could intervene and order Hong Kong officials not to surrender Snowden, citing "defense, foreign affairs or essential public interest or policy" reasons, per the treaty. Hong Kong is a special administrative region of China.
(2) The Chinese could also refuse to hand over Snowden if they believe an extradition request is "politically motivated," or designed to punish a suspect for "political opinion," or if they believe complying would deny him a fair trial, the agreement says.
Legal experts say refusing extradition under the aforementioned exceptions is rare, although not unprecedented, and highly unlikely, given implications for the U.S.-China bilateral relationship.
"The only thing I can do is sit here and hope the Hong Kong government does not deport me," Snowden, 29, said in his interview with U.K. newspaper The Guardian. "My predisposition is to seek asylum in a country with shared values. The nation that most encompasses this is Iceland."
Iceland might be a long shot. That country's ambassador to China told the South China Morning Post that Snowden would have to be physically inside Iceland in order to apply for such status.
"According to Icelandic law, a person can only submit such an application once he-she is in Iceland," Ambassador Kristín Árnadóttir said, according to the paper. "The Ministry of the Interior in Iceland deals with issues of this nature and handles applications for asylum."
However, one Icelandic lawmaker, Birgitta Jonsdottir, has already pledged to do everything she can to help Snowden.
"In relation to releasing this information to the public domain, [it] is very much in the spirit of like making a safe haven for freedom of information, expression, of speech, such we're working on in Iceland," Jonsdottir told ABC News.