Fifty-year-old Zina Roberson made her plea Monday in Franklin County court in central Ohio. She originally was indicted on a more serious count of aggravated murder.
A message seeking comment was left for her attorney.
Roberson lived in Rome, Georgia, for two decades before she was arrested. Investigators linked her DNA to evidence taken from the Columbus apartment where 77-year-old Anna Mae Florence was killed in 1987.
The Columbus Dispatch reports at the time of the murder, police said the suspect was a woman who knocked on Florence's door, claiming she was soliciting money for a charity benefiting the elderly.
Information from: The Columbus Dispatch, http://www.dispatch.com
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