CHICAGO — Two brothers who were said to have assaulted the actor Jussie Smollett in what the police called a staged hate crime filed a federal defamation lawsuit Tuesday against the entertainer’s legal team.

The brothers, Abimbola and Olabinjo Osundairo, said in the lawsuit that Mr. Smollett, an actor on “Empire,” orchestrated the fake attack against himself earlier this year and that two of the actor’s lawyers, Mark Geragos and Tina Glandian, then lied repeatedly about what happened.

“He wanted his employer and the public to notice and appreciate him as a successful black, openly gay actor,” the lawsuit said. “So, Mr. Smollett directed every aspect of the attack, including the location and the noose.”

The reported attack, which involved the use of a noose and bleach and took place on Jan. 29 in an upscale Chicago neighborhood near downtown, has held the attention of the city for months.