David Jackson

USA TODAY

WASHINGTON — As a growing number of lawmakers say there is no evidence to back his accusations against Barack Obama, President Trump is trying to alter the meaning of the term "wiretap."

Nearly two weeks after accusing Obama of wiretapping him during the run-up to last year's election — something that would be illegal — Trump and his aides are saying the term covers a variety of surveillance techniques.

"Wiretapping is pretty old-fashioned stuff," Trump told Fox News' Tucker Carlson in an interview Wednesday, echoing comments his aides have made in recent days. "But that really covers surveillance and many other things."

Bipartisan leaders of the Senate Intelligence Committee, meanwhile, said there is no evidence to back Trump's claims of wiretapping or surveillance.

“Based on the information available to us, we see no indications that Trump Tower was the subject of surveillance by any element of the United States government either before or after Election Day 2016," said the statement by Sen. Richard Burr, R-N.C., chairman of the intelligence panel, and Sen. Mark Warner of Virginia, the committee's top Democrat.

Rep. Devin Nunes, R-Calif., chairman of the House Intelligence Committee, said earlier this week that "I don’t believe that there was an actual tap of Trump Tower,” citing what he called "people that we’ve talked to."

If you take the president's tweets about wiretapping "literally," Nunes said, then the president is "wrong."

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House Speaker Paul Ryan, R-Wis., also threw cold water on Trump's theory, telling reporters Thursday: "We've cleared that up; we've seen no evidence of that."

Obama's spokesman has denied wiretapping, noting that presidents are prohibited by law from wiretapping and that such surveillance would have to be approved by a special court.

Trump's accusation, first made in a March 4 series of tweets, comes amid an investigation into whether the president or his associates had contacts with Russians involved in the effort to hack Democratic Party officials during last year's election. Trump has said he had nothing to do with Russia and described the probes as witchhunts.

The House Intelligence Committee, which has scheduled a hearing on the matter for Monday, has asked the Justice Department to supply information about Trump's wiretap claims.

In his Fox News interview, Trump said, "We will be submitting certain things and I will be perhaps speaking about this next week. But it's right now before the committee ... I have a lot of confidence in the committee."

Trump told Carlson he based his accusations on various news reports (as opposed to intelligence agencies).

In defending his expanded definition of the term wiretapping, Trump said he put term "in quotes" during his March 4 tweetstorm, and "that's a very important thing."

Trump did use the terms "'wires tapped'" and "'wire tapping'" in quotation marks, but also accused Obama of "tapping my phones" without using quotes.

For days, Trump aides have tried to shift the term "wiretapping" to "surveillance." White House press secretary Sean Spicer said, "I think there is significant reporting about surveillance techniques that have existed throughout the 2016 election."

News reports include claims that, while investigating Russian activity in the election, investigators looked at possible contacts between Russian officials and Trump associates. There are also news reports about a possible connection between a Russian bank and a computer at Trump Tower.

In any event, Spicer said there was no connection between the Trump campaign and Russians who sought to hack the 2016 election.

"There's nothing there," he said.