Skadden produced the 187-page report at the behest of Paul Manafort, the former chairman of Donald Trump's presidential campaign who is now serving a 7 1/2-year prison sentence for lobbying violations and financial crimes. "Mr. Craig is not guilty of any charge and the government's stubborn insistence on prosecuting Mr. Craig is a misguided abuse of prosecutorial discretion", Craig's lawyers said in a statement on the eve of his indictment.
The case against Craig stemmed from the wide-ranging probe overseen by Special Counsel Robert Mueller.
In a letter sent to the Justice Department in October 2013, and obtained by The Washington Post, Craig wrote that his media contacts came in response "to inaccuracies in US news reports" and that he was "in no way serving as an agent for Ukraine".
The report was billed as independent, and while critical in some ways of Tymoshenko's trial, critics have said it whitewashed a politically motivated prosecution.
Mueller's office referred Craig's case past year to prosecutors in Manhattan as Mueller worked to bring his investigation to a close.
His lobbying was allegedly linked to ex-Trump campaign chair Paul Manafort's political efforts in Ukraine.
Emails between members of the law firm indicated Craig was concerned about whether the lawyers would need to register under the FARA statute, according to the indictment.
"The only time we responded, was to correct misinformation", Craig wrote.
Craig, 74, is the highest-profile Democrat to be indicted in a matter stemming from Mueller's work, which resulted in charges against numerous Republicans connected to President Donald Trump.
According to the indictment, Craig covered up aspects of his work in order to avoid registering as a foreign agent under the Foreign Agents Registration Act (FARA), a rarely enforced law that was enacted in 1938 to counter Nazi propaganda. The charges come about three months after Craig's former law firm agreed to pay more than $4.6 million and publicly acknowledge that it failed to register with the government for its work for the Ukraine. The report was also presented to US government officials, raising questions if it constituted lobbying.
In the statement Wednesday, Craig's lawyers denied that he lied to the government or his firm.
Prosecutors say he misleadingly instructed his law firm - Skadden Arps Slate Meager & Flom - not to register under federal lobbying requirements because he feared being locked from future government positions.
The Ukrainian government reported that Skadden was paid $12,000 for the report, but prosecutors have said Manafort used an offshore account to help route more than $4 million to the law firm to pay for the work.
It criticized Tymoshenko's behavior during the trial and concluded that her due-process rights had not been violated, but also said that she had been improperly imprisoned during the trial. Alex van der Zwaan, a Belgian-born Dutch national, was sentenced to 30 days in prison in April 2018 for lying about his work related to the report.