After two years of studiously avoiding the spotlight, the special counsel, Robert Mueller, was finally ready to speak to the public. Standing at a lectern with a sign behind him that said “Department of Justice Washington,” he looked every inch the part: dark chalk-stripe suit, white button-down shirt, navy-blue tie, hair parted at the side, posture erect. His voice was firm, and his words were carefully chosen to put the onus firmly on Congress to decide whether to impeach Donald Trump on charges of obstruction of justice.

Volume II of the Mueller report, which the special counsel delivered to the Attorney General, William Barr, at the end of March, contained a section purporting to explain why Mueller decided not to reach a prosecutorial decision on whether Trump obstructed justice, but it was prolix and a bit difficult to decipher. This time around, Mueller made an effort to be shorter and clearer. He succeeded.

“The order appointing me special counsel authorized us to investigate actions that could obstruct the investigation,” Mueller said. “We conducted that investigation, and we kept the office of the Acting Attorney General apprised of the progress of our work. As set forth in our report, after that investigation, if we had confidence that the President clearly did not commit a crime, we would have said that.” (What it does say is “while this report does not conclude that the President committed a crime, it also does not exonerate him.”)

After stating that he and his colleagues couldn’t clear Trump, Mueller reiterated that they also didn’t make any determination “as to whether the President did commit a crime.” Then he explained the reasoning behind this omission. Under a long-standing Department of Justice policy, “a President cannot be charged with a federal crime while he is in office,” he said. “That is unconstitutional. Even if the charge is kept under seal and hidden from public view—that, too, is prohibited. The special counsel’s office is part of the Department of Justice, and, by regulation, it was bound by that department policy. Charging the President with a crime was therefore not an option we could consider.”

The Mueller report made extensive references to the Department of Justice guidelines about indicting a sitting President. Here, Mueller was being far more direct. Indicting a President while he is still in office was never an option that Mueller could even contemplate. Nor was the possibility of filing an indictment under seal, which could be unveiled after Trump left office. Why, then, bother to carry out the investigation at all?

Mueller provided two reasons, which he said were both contained in the department’s legal opinion explaining the policy that rules out charging a sitting President. “First . . . because it is important to preserve evidence while memories are fresh and documents are available . . . and second, the opinion says that the Constitution requires a process other than the criminal-justice system to formally accuse a sitting President of wrongdoing.”

What “process” would that be? Impeachment, of course. Without even uttering the I-word, Mueller appeared to be extending an invitation to Congress to carry out the task he was barred from doing: to weigh the evidence his investigators had gathered and reach a decision on whether it justified an indictment. In appealing directly to the Constitution, Mueller could hardly have been more transparent.

To be sure, Mueller also said that, “beyond department policy,” he and his colleagues were also motivated by fairness. “It would be unfair to potentially accuse somebody of a crime when there can be no court resolution of an actual charge,” he noted. But that, too, seemed like a pointer to an impeachment procedure, in which the President could and would launch a vigorous defense, and the ten instances of possible obstruction detailed in the Mueller report would be the primary focus of attention.

In closing, Mueller thanked his staff, some of whom Trump had repeatedly portrayed as “angry Democrats,” and said that they were “of the highest integrity.” He also expressed the (probably vain) hope that this would be his last public statement about the investigation, and again touted its findings, saying, “My report is my testimony. I would not provide information beyond that which is already public in any appearance before Congress.”

A couple of hours after Mueller’s appearance, Nancy Pelosi, the Democratic Speaker of the House, issued a statement in which she said, “Congress will continue to investigate and legislate to protect our elections and secure our democracy.” Pelosi didn’t mention impeachment. Jerry Nadler, the chairman of the House Judiciary Committee, merely said the option was “on the table.” Evidently, the Democratic leadership is still intent on pursuing a go-slow strategy for political reasons. Mueller’s statement has made that strategy harder to sustain.