As the European Parliament balks at a permanent Passenger Name Record agreement with the United States, officials from the Homeland Security Department touted the system's usefulness for preventing terrorism and defended its privacy record at a House Homeland Security subcommittee hearing Oct. 5.

The United States and European Union reached a provisional agreement in 2007 over the use of PNR data from flights with ties to E.U. countries. Though the provisional agreement is not scheduled to sunset until 2014, the European Union sought to renegotiate it in 2010 at the behest of its parliament, which is worried about privacy.

PNR data can include the passenger's contact information, payment method and itinerary, for example.

Mary Ellen Callahan, DHS's chief privacy officer, told the subcommittee that after conducting reviews, "the DHS privacy office found, and the E.U. acknowledged, that there has not been a single privacy incident or data breach involving the unauthorized use of PNR data."

DHS Assistant Secretary for Policy David Heyman added that use of PNR data is subject to independent oversight including from DHS's inspector general and the Government Accountability Office.

PNR data has proven its value repeatedly, said Thomas Bush, a Customs and Border Protection official. Bush credited PNR data for the arrests of David Headley, who helped plan the 2008 Mumbai terrorist attacks; Najibullah Zazi, who plotted to bomb New York City subways; and Faisal Shahzad, who tried to detonate a car bomb in New York's Times Square.

In the case of Shahzad, the FBI used his cell phone number to identify him via the PNR database, and then used departing passenger data and arrested him while he was attempting to flee the United States, according to joint written testimony from the officials.

Nonetheless, the European Parliament is committed to the legal concept of proportionality, broadly defined to mean that governments should collect the minimum amount of information needed and that they should only collect information from known criminals, Callahan explained.

But "we don't know who all the bad guys are," making it difficult to abide by those standards, she said.

For more:
- go to the hearing page to watch the hearing and view prepared testimony

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