WASHINGTON — US spy and law enforcement agencies were united in the belief, in the weeks before the presidential election, that the Russian government had deployed computer hackers to sow chaos during the campaign. But they had conflicting views about the specific goals of the subterfuge.
Last week, CIA officials presented lawmakers with a stunning new judgment that upended the debate: Russia, they said, had intervened with the primary aim of helping make Donald Trump president.
The CIA’s conclusion does not appear to be the product of specific new intelligence obtained since the election, several US officials, including some who had read the agency’s briefing, said on Sunday. Rather, it was an analysis of what many believe is overwhelming circumstantial evidence — evidence that others feel does not support firm judgments — that the Russians put a thumb on the scale for Trump, and got their desired outcome.
It is unclear why the CIA did not produce this formal assessment before the election, although several officials said that parts of it had been made available to President Obama in the presidential daily briefing in the weeks before the vote. But the conclusion that Moscow ran an operation to help install the next president is one of the most consequential analyses by US spy agencies in years.
Trump’s response has been to dismiss the reports by citing another famous intelligence assessment — the botched 2002 conclusion that the Iraqi leader, Saddam Hussein, had weapons of mass destruction — and portraying US spies as bumbling and biased.
“I think it’s ridiculous. I think it’s just another excuse. I don’t believe it,” Trump said Sunday in an interview on Fox News. He also indicated that as president, he would not take the daily intelligence briefing that Obama and his predecessors have received.
Trump, who has received the briefing sparingly as president-elect, said that it was often repetitive and that he would take it “when I need it.” He said his vice president, Mike Pence, would receive the briefing.
“You know, I’m, like, a smart person,” he said. “I don’t have to be told the same thing in the same words every single day for the next eight years.”
He added that he had instructed the officials who give the briefing: “ ‘If something should change from this point, immediately call me. I’m available on a one-minute’s notice.’ ”
Some top Republican congressmen have cast doubt on the latest intelligence assessment, although with less bombastic language, arguing that there is no clear proof that the Russians tried to rig the election for Trump.
Yet there is a loud chorus of bipartisan voices, including Senator John McCain, an Arizona Republican, going public to accuse the Russians of election interference.
Representative Adam B. Schiff of California, the top Democrat on the House Intelligence Committee, said the evidence made it clear that Moscow had intervened to help the “most ostentatiously pro-Russian candidate in history.”
“If the Russians were going to interfere, why on earth would they do it to the detriment of the candidate that was pro-Russian?” Schiff asked.
The dispute cuts to core realities of intelligence analysis. Judgments are often made in a fog of uncertainty, are sometimes based on putting together shards of a mosaic that do not reveal a full picture, and can always be affected by biases.
Both intelligence and law enforcement officials agree that there is a mountain of circumstantial evidence suggesting that the Russian hacking was primarily aimed at helping Trump and damaging his opponent, Hillary Clinton.
In July, the infiltration of the Democratic National Committee’s computer servers produced embarrassing e-mails and other internal party documents, the publication of which caused a backlash that led to the resignation of committee chairwoman Debbie Wasserman Schultz. Just weeks before the election, hacked e-mails from the account of John D. Podesta, Clinton’s campaign manager, were made public and produced stories about the internal dynamics of the campaign. That hack also produced the text of speeches Clinton had given to Wall Street banks.
US intelligence officials believe that Russia also penetrated databases housing Republican National Committee data, but chose to release documents only on the Democrats. The committee has denied that it was hacked.
Beyond the specific targets of the hacks, US officials cite broad evidence that the Russian government favored Trump over Clinton.
And yet, there is skepticism within the US government, particularly at the FBI, that this evidence adds up to proof that the Russians had the specific objective of getting Trump elected.
A senior US law enforcement official said the FBI believed that the Russians probably had a combination of goals, including damaging Clinton and undermining US democratic institutions. Whether one of those goals was to install Trump remains unclear to the FBI, he said.
The official played down any disagreement between the FBI and the CIA, and suggested that the CIA’s conclusions were probably more nuanced than they were being framed in the media.
The agencies’ differences in judgment may also reflect different methods of investigating the Russian interference. The FBI, which has both a law enforcement and an intelligence role, is held to higher standards of proof in examining people involved in the hacking because it has an eye toward eventual criminal prosecutions. The CIA has a broader mandate to develop intelligence assessments.
The FBI began investigating Russia’s apparent attempts to affect the election over the summer.
At the height of its investigation before the election, the FBI saw some indications that the Russians might be explicitly seeking to get Trump elected, officials said, and investigators collected online evidence and conducted interviews overseas and inside the United States to test that theory.
The FBI was concerned enough about Russia’s influence and possible connections to the Trump campaign that it briefed congressional leaders — including Harry Reid, a Nevada Democrat and the Senate minority leader — on some of the evidence this summer and fall. Reid, in particular, pressed for the FBI to find out more and charged that the agency was sitting on important information that could implicate Russia.
But the agency’s suspicions about a direct effort by Russia to help Trump, or about possible connections between the two camps, appear to have waned as the investigation continued into September and October. The reasons are not entirely clear, and FBI officials declined to comment.