Also excluded are entries in TIDE that are not specific enough to be useful for watchlisting purposes.
This complex and sprawling U.S. machinery for collecting, assessing and watchlisting information about suspected terrorists, established in the wake of the Sept. 11 terror attacks, has come under new scrutiny following the Boston Marathon bombing last month.
Accused Chechen-American bomber Tamerlan Tsarnaev was interviewed by the FBI in 2011, after Russian authorities said they were concerned he might be radicalizing and preparing to come to Russia to join Islamic extremist terror groups in the volatile Muslim-majority North Caucasus.
The FBI, who also interviewed relatives and trawled through Mr. Tsarnaev’s electronic communications, found no derogatory information and — after repeatedly requesting more details from the Russians and getting no response — closed their file, the bureau said last month.
While they were investigating him, the FBI listed him in TECS. But not as a terrorist, the senior intelligence official said.
The FBI determination at that time was that there was not sufficient derogatory information to consider Mr. Tsarnaev, a green card holder in the process of becoming a citizen, an “appropriately known or suspected terrorist,” the official said.
“They put him in TECS because they wanted to look at his travel history, not because” they thought he was a threat, the official said. He noted that law enforcement agencies can flag people for scrutiny when they travel abroad for a variety of non-terror related reasons, for example if they are suspected of involvement in drug or people smuggling, or they are believed to be a target or an operative of a foreign intelligence service.
The TECS listing caused what became “the ping heard ‘round the world.”
Homeland Security Secretary Janet Napolitano told Congress the week after the bombing that Mr. Tsarnaev had “pinged” in the DHS’ watchlist system when he left for Russia on a mysterious six-month visit which investigators believe may be crucial to understanding his motivation and capabilities for the bombing.
By the time he returned six months later, she said, the listing had lapsed because the FBI assessment had been closed.
The remarks prompted charges from lawmakers that U.S. intelligence agencies had once again failed to “connect the dots,” and thwart a terror plot in the making.
But last week, it emerged that both Mr. Tsarnaev and his mother Zubeidat Tsarnaeva, were entered into TIDE anyway, after the FBI had closed their investigation.
“The CIA knew the FBI had done a review, but out of an abundance of caution, they nominated him and his mother [to TIDE] anyway. Under the post-Abdulmutallab rules they were pushed to the TSDB,” he added.
Experts say the difference in the behavior of the two agencies is a classic example of how U.S. intelligence and law enforcement agencies — though they now work much more closely together on counter-terrorism — continue to have rather different approaches to the issue.