A man charged with killing his wife in a frenzied knife attack testified Monday that it was his 12-year-old daughter who committed the crime, but he said he tried to cover it up.

Brad Reay, 47, took the stand at his trial in the slaying of his wife, Tami, after prosecutors rested their case Monday morning.

Their daughter, Haylee, testified last week, denying her father's claims that she killed her mother.

The nude body of Tami Reay, 41, was found near Lake Oahe outside Pierre two days after she disappeared last February. Authorities said some of the wounds in her chest showed a knife had been forced in all the way to its hilt.

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Reay told jurors that he did not know before his wife was killed in the family home that she was having an affair, but he said they had discussed splitting up. He said his daughter was extremely upset after they told her about the possibility of divorce.

Reay said he awoke in the night to find his daughter standing over her mother in the woman's bedroom. His daughter had a knife in her hand, he said.

Haylee was "catatonic or in shock" and did not respond when he asked her what she'd done, he said.

Reay said his daughter did not recover from that state until after he had cleaned blood off her and placed her in bed.

Then, he said, "She just kind of looked at me like she didn't know what I was talking about."

Reay said he tried to make his wife's death look like she had been raped in order to divert attention from his daughter.

"I plan to go to jail for her," he said. "I didn't want her to get in trouble."

Haylee, now 13, testified last week that she never would have hurt her mother, and said she was afraid of her father and had never been very close to him.

Jurors could find Reay guilty of either first-degree murder, punishable by a mandatory term of life in prison without chance of parole, or manslaughter, which carries a sentence of up to life in prison. Prosecutors are not seeking the death penalty.