McCaul said he was "amazed" about the rush in which people are concluding there is no foreign connection to brothers Tamerlan and Dzhokhar Tsarnaev, especially given the elder brother’s trip to Russia.
He said authorities don’t know what Tamerlan Tsarnaev, who was killed after a gunbattle with police, did or who he met with on his trip.
"What I'm a little bit amazed about is this rush to judgment that there's no foreign connection at all when the FBI, in their own words, have just started this investigation,” McCaul said in an interview on MSNBC.
"I mean they are just now scrubbing his computers, the older brother's. They are finally interviewing people overseas, and so I think it's way too premature about coming to conclusions about whether there's a foreign connection or not," he said.
McCaul also said he wanted to know what information, if any, on the brothers was shared between law enforcement agencies.
"We talked a lot about connecting the dots … after 9/11, and we are 12 years later, and the fact remains that it's still not working," McCaul said. "What I'd like to know is whether or not the Department of Homeland Security shared that information with the FBI and the Joint Terrorism Task Force that possibly could have led to opening this lead investigation back up on the older brother."
Tamerlan had been on law enforcement's radar for a while, which should have “popped up,” McCaul added.
The FBI reportedly investigated Tamerlan in 2011 in response to a request by the Russian government, but the probe did not turn up troublesome information. On Monday Sen. Lindsey Graham (R-S.C.) said that Tamerlan went undetected by federal authorities because of a misspelling of his name.
McCaul said Tamerlan Tsarnaev’s name should have popped up on terrorist watch list.
"I wouldn't say this is a comedy of errors, but there have been a lot of information of clerical errors that prevented that information," he said.