Former special counsel Robert Mueller's nearly two-year investigation into Russia's election interference cost $31.7 million, according to the Department of Justice.

The special counsel's office directly spent about $16.4 million since it was brought into the fold in May 2017. Mueller spent approximately $6.56 million in the last eight months of the probe, of which $4.12 million was personally spent from the special counsel's office, and the Justice Department used up $2.44 million to assist Mueller's work, according to CNBC.

The nearly $32 million price tag, Politico reports, covered all expenditures through May 31, two months after Mueller wrapped up his investigation and the Justice Department released his 448-page report, with redactions, detailing Russia's interference in the 2016 presidential election, but did not find a criminal conspiracy between the Russian government and the Trump campaign.

Though Mueller's investigation carried an expensive cost, DOJ officials would have accrued $15.3 million throughout the inquiry regardless if Mueller had been brought in to serve as special counsel. The biggest component of Mueller's receipts covered salaries and benefits, with $9.7 million allocated to the various lawyers, FBI agents, intelligence analysts, forensic accountants, and other personnel who assisted with the investigation.

Mueller's office also revealed it spent $3.1 million on rent, communications, and utilities, and $1.6 million was allocated for travel and personal transportation.

President Trump often complained that the special counsel's investigation, which he called a "witch hunt," would cost more than $40 million.

"When will this illegal Joseph McCarthy style Witch Hunt, one that has shattered so many innocent lives, ever end-or will it just go on forever?" Trump tweeted in November. "After wasting more than $40,000,000 (is that possible?), it has proven only one thing-there was NO Collusion with Russia. So Ridiculous!"

When will this illegal Joseph McCarthy style Witch Hunt, one that has shattered so many innocent lives, ever end-or will it just go on forever? After wasting more than $40,000,000 (is that possible?), it has proven only one thing-there was NO Collusion with Russia. So Ridiculous! — Donald J. Trump (@realDonaldTrump) November 29, 2018

Some Democrats, such as House Judiciary Chairman Jerry Nadler, asserted that the criminal indictments of numerous individuals throughout the investigation and subsequent forfeiture of millions of dollars in personal assets effectively counteracted the total cost of the investigation.

"You secured the convictions of President Trump’s campaign chairman, his deputy campaign manager, his national security adviser, and his personal lawyer, among others," the New York Democrat said before Mueller’s high-profile testimony last month. "In the Paul Manafort case alone, you recovered as much as $42 million, so that the cost of your investigation to the taxpayers approaches zero."

It is estimated that as much as $42 million was confiscated from former Trump campaign chairman Paul Manafort, who was convicted and later entered a plea deal in which he lost much of his real estate, bank accounts, and a life insurance policy.

Mueller brought more than 100 charges against three Russian companies and 34 people, including several former Trump advisers, during the investigation, which lasted from May 2017 until March 2019, although none of them had to do with conspiracy.