“Mr. Murphy followed proper, lawful whistle-blower rules in reporting serious allegations of misconduct against D.H.S. leadership, particularly involving political distortion of intelligence analysis and retaliation,” Mark S. Zaid, Mr. Murphy’s lawyer, said in a statement.
Democrats on the House Intelligence Committee asked Mr. Murphy to testify in private on Sept. 21, a possible precursor to a public hearing in the weeks before Election Day.
“We will get to the bottom of this, expose any and all misconduct or corruption to the American people, and put a stop to the politicization of intelligence,” said Representative Adam B. Schiff, Democrat of California and the chairman of the committee. He said the allegations of politically censored intelligence assessments were particularly worrisome in light of the Trump administration’s decision last month to stop briefing lawmakers in person on election security threats.
Sarah Matthews, a White House spokeswoman, said in a statement that Mr. O’Brien had “never sought to dictate the intelligence community’s focus on threats to the integrity of our elections or on any other topic.” She called Mr. Murphy a “disgruntled former employee” whom Mr. O’Brien had never heard of. But, she added, the national security adviser “consistently and publicly advocated for a holistic focus on all threats to our elections — whether from Russia, Iran, China or any other malign actor.”
Alexei Woltornist, the spokesman for the Homeland Security Department, rejected Mr. Murphy’s allegations.
“We flatly deny that there is any truth to the merits of Mr. Murphy’s claim,” Mr. Woltornist said. “D.H.S. looks forward to the results of any resulting investigation, and we expect it will conclude that no retaliatory action was taken against Mr. Murphy.”
As president, Mr. Trump has clashed frequently with the intelligence community, particularly over the issue of election interference. At a news conference in 2018 in Helsinki, Finland, Mr. Trump sided with President Vladimir V. Putin of Russia and said he did not think Moscow was responsible for the 2016 interference. A few months later, Mr. Trump dismissed the C.I.A.’s assessment that the Saudi crown prince was responsible for the murder of Jamal Khashoggi, a prominent Washington Post columnist. In February 2019, after intelligence chiefs offered Congress assessments on North Korea and Iran that were at odds with the White House, the president told them to “go back to school.”