Donald Trump had decried the special counsel’s work as a ‘witch-hunt’ but the convictions of his ex-campaign chair and former fixer suggest otherwise

For more than a year, Donald Trump has been trying to tear down the Robert Mueller investigation, attacking its officers, impugning its motives and raising the cry “witch-hunt”.

Paul Manafort: Trump's ex-campaign chair guilty on eight counts of fraud Read more

But Mueller struck back on Tuesday, in his silent yet forceful way, winning guilty verdicts in the criminal fraud trial of the former Trump campaign chairman Paul Manafort and possibly sending Manafort to prison for the rest of his life.

A Virginia jury found Manafort, 69, guilty of bank fraud, tax fraud and failure to report a foreign bank account.

In a separate court action in New York, former Trump personal lawyer Michael Cohen pleaded guilty to eight federal crimes on Tuesday and said Trump had directed him to make two hush-money payments to women in violation of campaign finance laws. That case was referred to New York prosecutors by Mueller.

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For Trump, the implications of the Manafort conviction and Cohen plea are ominous. In convicting Manafort, Mueller has won new impetus to prosecute figures even closer to Trump, should the evidence warrant.

For Mueller’s team, the guilty verdict represents a substantial victory, a significant hurdle cleared. The case was Mueller’s first outing at trial, and a failure to convict might have called into question Mueller’s broader enterprise.

Michael Cohen, Trump's former lawyer, pleads guilty in New York court Read more

The White House did not have immediate reaction to the verdict. Trump called the Manafort verdict a “disgrace” and portrayed it as an unnatural outgrowth of the Russia investigation, when in fact the FBI investigation of Manafort predated the 2016 presidential campaign and was subsequently folded into Mueller’s caseload.

The Manafort conviction and, to a lesser extent, the Cohen plea deal, have changed the dynamics of Trump’s public campaign against Mueller, however. Until now, Trump’s attacks on the Mueller team could potentially be seen as mere political jousting.

But with a jury of fellow Americans now having unanimously decided that Manafort broke the law, Trump’s attacks on Mueller begin to look more like a personal beef on the president’s part with the American system of crime and punishment, analysts said.

The justice department commissioned Mueller in May 2017 to investigate “any links and/or coordination between the Russian government and individuals associated with the campaign of President Donald Trump” and related matters.

Before the Manafort conviction, Mueller had secured guilty pleas from three former Trump aides – Rick Gates, George Papadopoulos and Michael Flynn. Manafort, in contrast, decided to take his chances in court instead of seeking a plea deal, assuming that one was available to him.

Significantly, Manafort’s trial did not go to the heart of the Mueller investigation of the campaign’s Russia ties. Similarly, none of the Mueller indictments so far features an extensive exploration of those ties based on the testimony of the three known cooperating witnesses who worked on the campaign.

Facebook Twitter Pinterest Donald Trump speaks to the news media on the airport tarmac about the conviction of Paul Manafort. Photograph: Leah Millis/Reuters

The resulting sense is that Mueller has at least one big play left to make. If not, he may be preparing a description of why further charges were not warranted, in deference to the approximately six in 10 Americans who consider the Russia investigation to be a serious matter worthy of investigation.

The Trump camp has recently stepped up its efforts to impose an arbitrary deadline on Mueller’s work, with spokesman Rudy Giuliani calling on Mueller to submit a report by 7 September, to allow for a cushion before the midterm elections in November.

“If he doesn’t get it done in the next two or three weeks we will just unload on him like a ton of bricks,” Giuliani told Bloomberg, adding: “Write the damn report so we can see it and rebut it.”

In fact, Mueller’s investigation has produced more guilty pleas, faster, than any comparable prior investigation, according to a FiveThirtyEight analysis of 10 special investigations since 1979.

But the Trump camp’s attempt to apply deadline pressure on Mueller appears to be working. Two-thirds of respondents told a CNN poll conducted by SSRS in the second week of August that Mueller should complete the investigation before November.

The public has not bought Trump’s “witch-hunt” argument, however, according to the poll, with 70% saying Trump should testify in the special counsel investigation. Months of negotiations between Mueller and the White House to make that happen have so far proven fruitless.

Looming over the timeline, for Mueller, is the example of the FBI director James Comey, whose high-profile updates during the 2016 presidential election on an investigation of Hillary Clinton’s email hygiene were blamed by Clinton for her election loss.

Mueller would want to avoid vulnerability to similar charges of influencing an election.

If Mueller does not conclude his investigation quickly, Trump might make good on Giuliani’s vow to “unload on him”. Unfortunately for Trump, it’s not clear that the public would be impressed by such a show. With the Manafort conviction, Mueller appears more than ever to have the law on his side.