Washington CNN  — 

President Donald Trump on Wednesday downplayed the allegations facing his former campaign chairman, Paul Manafort, by invoking notorious mobster Al Capone.

“Looking back on history, who was treated worse, Alfonse Capone, legendary mob boss, killer and ‘Public Enemy Number One,’ or Paul Manafort, political operative & Reagan/Dole darling, now serving solitary confinement - although convicted of nothing?” Trump tweeted Wednesday, incorrectly spelling the gangster’s first name.

He added, “Where is the Russian Collusion?”

Manafort’s own attorneys, however, have described him as being kept in “solitary confinement” for his own safety.

Trump did not go as far as to say Manafort is innocent. The President and the White House have repeatedly noted that the bank fraud and tax evasion charges Manafort faces deal with actions that allegedly took place before he was involved in Trump’s 2016 campaign. They’ve also sought to downplay his role with the Trump campaign, saying he was at the helm for only a few months, even though he was chairman during the critical convention and delegate process.

Mueller is investigating Russian interference in the 2016 election and potential coordination between Trump campaign associates and Russia, though his mandate allows him to investigate “any matters that arose or may arise” from the Russia investigation.

Trump’s question posed on Twitter comes on the second day of Manafort’s trial in federal court. He has plead not guilty to all charges.

There is one thing Capone and Manafort have in common: both were charged with tax evasion. Capone was convicted in 1931 and sentenced to 11 years in federal prison.