Trevor Hughes/USA Today Network
Mourners created a memorial outside Sonya Massey’s home, where she was killed by a sheriff’s deputy.
CNN  — 

By the time then-sheriff’s Deputy Sean Grayson gunned down a 36-year-old mother in her home, fellow law enforcement officers and residents in the Illinois communities he served had already raised a host of concerns about him.

Grayson, 30, is now charged with murder in the July 6 death of Sonya Massey; he has pleaded not guilty. Massey, a mother of two, joined Breonna Taylor and Atatiana Jefferson on a list of Black women killed in their own homes by law enforcement – whose deadly use of force came under scrutiny.

Massey’s death has led to renewed calls for a national, comprehensive database for tracking officers’ disciplinary issues or criminal offenses.

Sangamon County Jail/WISC
Sean Grayson, a former deputy with the Sangamon County Sheriff’s Office in Illinois, faces charges in the shooting death of Sonya Massey.

“Sonya Massey lost her life due to an unjustifiable and reckless decision by former Deputy Sean Grayson,” the Sangamon County sheriff said in a statement after firing Grayson.

An attorney representing Grayson, Daniel Fultz, declined to comment to CNN for this story.

Now, more details are emerging about Grayson’s alleged misconduct prior to killing Massey. Here’s a timeline of some of Grayson’s issues with the law, the military and his work in policing – which spanned six agencies in four years:

View this interactive content on CNN.com