WASHINGTON — The special counsel, Robert S. Mueller III, has delivered a report on his inquiry into Russian interference in the 2016 election to Attorney General William P. Barr, according to the Justice Department, bringing to an apparent close an investigation that has consumed the nation and cast a shadow over President Trump for nearly two years.

Mr. Barr will decide how much of the report to share with Congress and, by extension, the American public. The House voted unanimouslyin March on a nonbinding resolution to make public the report’s findings, an indication of the deep support within both parties to air whatever evidence prosecutors uncovered.

Since Mr. Mueller’s appointment in May 2017, his team has focused on how Russian operatives sought to sway the outcome of the 2016 presidential race and whether anyone tied to the Trump campaign, wittingly or unwittingly, cooperated with them. While the inquiry, started months earlier by the F.B.I., unearthed a far-ranging Russian influence operation, no public evidence has emerged that the president or his aides illegally assisted it.

Nonetheless, the damage to Mr. Trump and those in his circle has been extensive. A half-dozen former Trump aides have been indicted or convicted of crimes, mostly for lying to federal investigators or Congress. Others remain under investigation in cases that Mr. Mueller’s office handed off to federal prosecutors in New York and elsewhere. Dozens of Russian intelligence officers or citizens, along with three Russian companies, were charged in cases that are likely to languish in court because the defendants cannot be extradited to the United States.

Even though Mr. Mueller’s report is complete, some aspects of his inquiry remain active and may be overseen by the same prosecutors once they are reassigned to their old jobs within the Justice Department. For instance, recently filed court documents suggest that investigators are still examining why the former Trump campaign chairman Paul Manafort turned over campaign polling data in 2016 to a Russian associate whom prosecutors said was tied to Russian intelligence.

Mr. Mueller looked extensively at whether Mr. Trump obstructed justice to protect himself or his associates. But despite months of negotiations, prosecutors were unable to personally interview the president.

Mr. Trump’s lawyers insisted that he respond only to written questions from the special counsel. Even though under current Justice Department policy a sitting president cannot be indicted, Mr. Trump’s lawyers worried that his responses in an oral interview could bring political repercussions, including impeachment, or put him in legal jeopardy once he is out of office.

Not since Watergate has a special prosecutor’s inquiry so mesmerized the American public. Mr. Trump has helped make Mr. Mueller a household name, attacking his investigation an average of about twice a day as an unfair, politically motivated attempt to invalidate his election. He never forgave former Attorney General Jeff Sessions for recusing himself from the Russia inquiry, an action that cleared the way for his deputy, Rod J. Rosenstein, to appoint Mr. Mueller.

Mr. Trump reiterated his attacks on the special counsel this week, saying Mr. Mueller decided “out of the blue” to write a report, ignoring that regulations require him to do so. But the president also said the report should be made public because of “tens of millions” of Americans would want to know what it contains.

“Let people see it,” Mr. Trump said. “There was no collusion. There was no obstruction. There was no nothing.”

In court, the evidence amassed by the Mueller team has held up. Every defendant who is not still awaiting trial either pleaded guilty or was convicted by a jury. Although no American has been charged with illegally plotting with the Russians to tilt the election, Mr. Mueller uncovered a web of lies by former Trump aides. Read more at NY Times