She is a graduate of Randolph-Macon Woman's College and received her master's degree from George Washington University. She was a presidential appointee and worked in The White House and the Department of Commerce before moving into the private sector. As a financial analyst and marketing director, she worked for several defense and aerospace contractors.

After moving to Nashville, Ellison began research on a passion: forensics and crime. She has worked with the Metro Nashville Police Department, the FBI, and various other law enforcement organizations to research her books.

Her short stories have been widely published, including her award winning story "Prodigal Me" in the anthology Killer Year: Stories to Die For, edited by Lee Child.

She is the Friday columnist at the Anthony Award nominated blog Murderati and is a founding member of Killer Year, an organization dedicated to raising awareness for the debut novelists of 2007.

Ellison is a member of several writing organizations, including International Thriller Writers, Mystery Writers of America, Romance Writers of America and Sisters in Crime.

She lives in Nashville with her husband and a poorly trained cat.