Maureen was close friends with Jane Vasko and they went to the police academy together. Afterwords Maureen married and changed her name to Maureen Fernandez. She also became a detective and her friend Jane did as well. Their first mission as partners was to bring down the Blanco Brothers. It went horribly wrong.
While undercover Maureen saw a news report that claimed her husband had been shot. She ran out leaving Jane exposed. When Maureen got to the hospital she found out her husband was dead and shortly after she found out her partner Jane was in a coma due to a drug cocktail they gave her.
Jane was in a coma for over a year and Maureen kept vigil by her side. When Jane came out of the coma she found the life she had no longer existed and she wanted revenge against the Blanco Brothers.Maureen helped train her and get her body back in physical condition she also helped cover up her even being alive by getting a doctor to claim a Jane Doe was Jane. Lastly, Jane found out that the drug cocktail she was given gave her the ability to heal quickly. With the help from Maureen, Jane adopted a new moniker as Painkiller Jane.
Maureen continues to help Jane as a police detective. They have a very symbiotic relationship and help each other do what the other one cannot. She once used Jane to eliminate three generations of men who were torturing and eliminating young woman.
Theses were the men in the Fitzgerald family who over the years killed hundreds of young girls and because they were millionaires they were able to get away with it. Maureen knew that much of the force was on the payroll of the Fitzgerald family and that she couldn't do anything about it. Jane on the other-hand eventually eliminated every one of these criminals.
In the Painkiller Jane television show, Maureen's name is changed to Maureen Bowers and she works at a DEA.