Investigators believe she killed George Richardson jr at his home near near Nampa last week.
The Canyon County sheriff's office says the two left a bar together and went to his home. They say she shot and killed Richardson and stole his Jeep, sinking it in the Snake River just 2 miles from her Melba home.
In jail for an unrelated charge, police say Kirtley admitted to another inmate that she killed someone.
Kirtley also has a felony DUI warrant in Ada County.
The judge set her bond at $5 million dollars at her arraignment on Monday afternoon. She is scheduled to be back in court on February 20th.