LOS ANGELES (AP) — A federal judge under scrutiny for posting sexually explicit material on his own Web site declared a mistrial Friday in an obscenity trial over which he was presiding.

Judge Alex Kozinski said he would ask that the case be assigned to another judge.

Kozinski is chief judge of the 9th U.S. Circuit Court of Appeals but was serving as a trial judge in a federal obscenity prosecution of a man who distributed videos showing bestiality and extreme fetishes.

“In light of the public controversy surrounding my involvement in this case, I have concluded that there is a manifest necessity to declare a mistrial,” Kozinski wrote in his order.

The postings on the judge’s Web site came to light earlier this week when opening statements were under way. The trial was suspended Wednesday after jurors had already watched some of the videos.

Kozinski on Thursday asked an ethics panel of the 9th Circuit to conduct an investigation of his own conduct and pledged to cooperate fully. He also asked Supreme Court Chief Justice John Roberts to assign the inquiry to a panel of judges outside the 9th Circuit’s jurisdiction of nine western states.

In the obscenity case, the U.S. Department of Justice is prosecuting Ira Isaacs, 57, on four counts, including importation or transportation of obscene material for sale. He faces a maximum of 20 years in prison and forfeiture of assets if convicted.

Defense attorney Roger Jon Diamond said he was very upset about the mistrial and was considering his options.

He said it was unclear whether the case could proceed with the same jury and a new judge.

Diamond accused the Department of Justice of “intimidating Judge Kozinski into doing this.” Justice Department attorneys are trying the case.

“We all have to be nervous and concerned when the executive branch can do this to anybody, including the sitting federal appeals judge,” Diamond said.