WASHINGTON — Last July 24, Robert S. Mueller III, the special counsel who had investigated President Donald Trump’s 2016 campaign, told Congress that he had not found conclusive evidence of collusion with Russia and could not charge the president with obstructing justice under Justice Department guidelines.

That was enough for Trump to declare victory. “A great day for me,” he crowed.

The next morning, he telephoned the president of Ukraine and asked him to investigate Joe Biden. “I would like you to do us a favor,” he asked.

The Senate acquitted Trump Wednesday in the impeachment trial that grew out of that telephone call.

There’s every reason to expect that history will repeat itself.

After declaring his complete exoneration, he’ll resume asking foreign governments to help his reelection campaign.

That’s not a partisan prediction. The president and his lawyers spent much of the last few weeks arguing that his calls for Ukraine and China to investigate Biden’s son Hunter were not merely legal, but in the public interest.

“It’s relevant information for the voters to know,” White House lawyer Patrick Philbin told the Senate.

Under that logic, the president practically has a duty to ask other countries to dig up dirt on anyone who runs against him.

If he wanted to be consistent, Trump should also ask Russia’s FSB, the successor to the KGB, to release its files on his own past, since voters might find that information useful too. That doesn’t seem likely.

Anyway, what’s to stop him? Not much.

“He’s expressed no remorse or understanding that he did anything wrong,” said Sen. Angus King, an independent from Maine who usually votes with Democrats. “So why should he hold back? That’s what worries me.”

In an election year, the temptation for any president to bend the rules only grows, and Trump is not just any president.

That’s why it’s important for the Democratic-led House — and any Senate Republicans who still care — to shake off impeachment fatigue and subject Trump to tougher oversight than ever before.

There are plenty of vehicles. Congress still has a dozen or more investigations under way. So do federal and state prosecutors in New York. And the president faces several lawsuits brought by Congress and outside organizations.

There may be more whistleblowers like the still-unidentified intelligence officer who raised the alarm about Trump’s July 25 call to Ukraine’s president, Volodymyr Zelenskiy, if the president’s lieutenants don’t root them out.

If all else fails, there will be more tell-all memoirs from former administration officials, beginning with the book his former national security adviser John Bolton hopes to publish next month over White House resistance.

The House Intelligence Committee, led by impeachment prosecutor Rep. Adam B. Schiff, D-Calif., appears likely to subpoena Bolton soon to answer unresolved questions about the Ukraine affair. Schiff has suggested that he’ll make an announcement after the impeachment trial ends.

Other investigations run the gamut from potential high crimes to comparative misdemeanors.

Before impeachment, several House committees were investigating Trump’s entanglements with Russia; those probes never ended.

Other panels were looking into possible election law violations and the perennial question of whether the Trump Organization, Trump’s family business, is illegally profiting from his presidency.

House committees are also in federal court, suing to get access to Trump’s tax returns and to force testimony from former White House counsel Don McGahn.

In an unusual flash of bipartisanship, a Senate committee is investigating the complaint of a whistleblower in the Internal Revenue Service who reportedly alleged that a Trump political appointee interfered with the IRS audit of the president’s tax returns.

Federal and state prosecutors in New York are looking into allegations of fraud against the Trump Organization and illegal foreign donations to a pro-Trump political action committee. Those are the charges against Lev Parnas and Igor Fruman, two Soviet-born associates of Trump’s personal lawyer, Rudolph W. Giuliani.

So the president’s lawyers will have plenty of business.

All presidencies produce scandals of some kind — at least in the eyes of their opponents. Trump, who likes to claim he has accomplished more in three years than any of his predecessors, has produced more scandals than anyone since Richard Nixon.

If Trump wins a second term and continues abusing his office, we may see history repeat itself again.

It’s entirely possible that by 2022 or so, Trump could enter history with a unique accomplishment: the first president to be impeached twice.

Doyle McManus is a Los Angeles Times columnist.