Lawmakers should consider increasing the amount of time that terror suspects are tracked in federal databases, according to a Republican chairman.

House Homeland Security Committee Chairman Michael McCaul (R-Texas) said lawmakers might need to require U.S. agencies to keep suspects in databases for longer as a result of the Boston Marathon bombings.

“We’re going to have to look at — in term of investigatively — how we keep these leads on file, maybe keep the databases on file a little bit longer, and how we could keep people like that out of the United States,” McCaul said on Friday.

Last year, Boston bombing suspect Tamerlan Tsarnaev was reportedly added to a database of suspected and known terrorists maintained by the National Counterterrorism Center (NCTC).

The listing came after Russian authorities asked U.S. officials to investigate the Chechen-born American resident for possible radical ties.

But by the time the Tsarnaev returned from a 6-month trip to Russia in 2012, the United States had closed its investigations of him and customs officials cleared his reentry without much scrutiny, according to testimony this week from Homeland Security Secretary Janet Napolitano.

It’s unclear whether the FBI was ever notified that Tsarnaev’s name had been added to the Terrorist Identities Datamart Environment (TIDE).

McCaul is one of several lawmakers to propose changes to the intelligence system in the wake of the bombings that killed 3 people and wounded more than 200. Several members have suggested exploring a legislative approach to strengthening the FBI’s investigative reach, so it can more easily monitor the online activity of American terror suspects.

Speaking to the Republican National Lawyers Association at the National Press Club on Friday, McCaul said one of the “most offensive” aspects of the bombings was that Tamerlan Tsarnaev and his younger brother, Dzhokhar, came to the country as political refugees from Chechnya.

“One of the most offensive things about the Boston bombing to me, is that we let these people into this country under political asylum — because this country is the greatest country, and they wanted to come here for political asylum — and then they turned around and killed Americans,” said McCaul. “That is one of the most highly offensive things about this.”