Donald Trump has called the Jussie Smollett incident an "embarrassment", days after all disorderly conduct charges were dropped against the actor.
Prosecutors had alleged the Empire star had lied to police about being subjected to a hate crime attack.
The US president tweeted: "FBI & DOJ (Department of Justice) to review the outrageous Jussie Smollett case in Chicago.
"It is an embarrassment to our Nation!"
Mr Trump's comment came after it was reported that the FBI would investigate the case against Smollett, who insists he is innocent.
Smollett's lawyer has accused authorities of "continuing their campaign" against him, despite the charges being dropped.
Patricia Holmes said "the case is closed" and "no public official has the right to violate" her client's "due process rights".
Ms Holmes said Smollett "is innocent until proven guilty in the court of law".
"We respectfully request all government agencies involved live up to the ethical tenets of their office.
"The case was dismissed. We should allow Mr Smollett to move on with his life as a free citizen."
Authorities still believe Smollett filed a false police report alleging he was the victim of a racist and homophobic attack in Chicago on January 29.
The 36-year-old actor alleged two men beat him up and put a noose around his neck.
Police accused him of making it up, and he was charged with 16 counts of disorderly conduct.
Chicago Mayor Rahm Emanuel called the dropping of charges "a whitewash of justice" and lashed out at Smollett for dragging the city's reputation "through the mud".
Prosecutor Joseph Magats told reporters that officials dropped the case after Smollett forfeited a $10,000 (€8,900) bond payment and carried out community service.
The state alleged at the time that Smollett staged a false attack because he was unhappy with his salary on musical drama Empire and wanted to raise his profile.