I guess by most standards, this isn't a cold case, but anyway...
In the early morning hours of November 12th 1976, a fire broke out in southern Moose Jaw, Saskatchewan, Canada. When firefighters put out the fire, they discovered a body. They initally thought the deceased died because of the fire. Getting a closer look, the small female body more than 100 stab wounds. The woman, who turned out to be Dr. Isabellita Joven, had her head smashed in as well.
Pretty soon cops found a suspect, Laura Ann Schepens. Schepens led police to a metal bar, a blood soaked towel from Dr. Joven's house, Schepens' gloves and clothing worn on the night of the murder--both covered in blood. The bar was found in a dirt pile near Schepens' house. When the police went to her house, they found out she had been courting Dr. Joven's fiancee. Schepens also made comments that 'the pigs are here', that if she was put in jail she'd shoot herself. She also threw a kitchen knife on the counter saying, "I suppose this is what you are looking for."
She said on the night of the murder, she was driving near Dr. Joven's house and saw it was ablaze. She went in the house (the door was unlocked) and found the doctor on the floor. In "great fright", Schepens said she fell onto the body, thus explaining why her clothes worn on that night were bloody.
For some bizarre reason, Laura Ann Schepens was never put in jail for this, although in my opinion, there is quite a bit of evidence.