A man who police say killed his wife in their suburban Detroit home, dismembered her and deposited her body parts in a nearby park was arraigned Tuesday on charges of first-degree murder and dismemberment of a body.

Stephen Grant, who a day earlier was released from a northern Michigan hospital after being treated for frostbite and hypothermia, entered the courtroom at the Macomb County Jail in a wheelchair, and Judge Denis LeDuc entered a not guilty plea on his behalf.

The 37-year-old is charged in the death of his wife, Tara Lynn Grant, after three weeks of steadfastly maintaining his innocence then offering what authorities say was a lengthy, graphic confession.

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LeDuc ordered that Grant be held without bond and scheduled a preliminary examination for March 20.

Grant had no attorney at the arraignment. David Griem, a lawyer who had acted as Grant's spokesman, said Sunday he no longer would represent Grant because of irreconcilable differences. The judge said he would appoint a lawyer for Grant.

LeDuc approved the prosecutor's request that the charges against Grant be amended to include first-degree, or premeditated, murder, which is punishable by life in prison without the possibility of parole upon conviction. Macomb County Prosecutor Eric Smith said the charge was warranted, because an autopsy indicates that Tara Grant died of manual strangulation, in which the victim typically takes five minutes to die.

Grant answered the judge's questions politely during Tuesday's brief hearing, telling LeDuc his full name, his address and that he was not represented by counsel.

"Mr. Grant, I don't think I need to hear anything further with regard to the issue of bond," the judge said. "Given the extreme, extreme seriousness of the charges, the nature of the allegations here, the nature of the alleged flight, the court agrees with the people. I'm going to order you held without bond. Do you understand that?"

"Yes, your honor," Grant replied.