DETROIT — The former top aide to Mayor Kwame Kilpatrick of Detroit chose to go to trial today, rejecting prosecutors’ offers that included pleading guilty to two felony counts and serving at least 60 days in jail in a City Hall sex scandal.

Christine Beatty turned down a plea offer that called for 60 days in jail and another that required 150 days, the Assistant Wayne County Prosecutor, Robert Spada, told a judge.

The longer sentence emerged in the latest offer Friday after Ms. Beatty rejected the shorter punishment Thursday, Mr. Spada said.

“The offer is rejected,” her defense attorney, Mayer Morganroth, told Wayne County Circuit Judge David Groner.

Judge Groner said he worked for three hours to bring both sides to an agreement.

“Everything was overly harsh. You know that because there was no acceptance,” Mr. Morganroth told reporters outside court.

There was no comment from prosecutors. Circuit Judge Timothy Kenny was tapped as the trial judge, and a pre-trial hearing was scheduled for Friday.

In March, Ms. Beatty was charged with perjury and obstruction of justice. She and Mr. Kilpatrick were accused of lying when they denied an affair during testimony in a lawsuit filed by ex-police officers.

Sexually explicit text messages first published by the Detroit Free Press contradicted those denials. Mr. Kilpatrick, a Democrat, already has pleaded guilty and leaves office Thursday. He goes to jail for four months in late October.