FORT COLLINS, Colo. (CBS4) – Investigators in Fort Collins are trying to piece together the events that happened before a 20-year-old woman slashed her boyfriend’s throat with a beer bottle.

The incident happened on Oct. 2 and the boyfriend, Shaun Cassidy, 23, of Montrose, died on Sunday. CBS4 is not reporting the name of the woman while the case is pending.

Prosecutors are now trying to determine what charges, if any, to bring.

Colorado’s Make My Day Law protects suspects who are defending themselves inside their home, and it could possibly apply in this case.

Neighbors CBS4 talked to say from their perspective it may not be a clear open-and-shut case for the district attorney’s office.

The incident happened at an apartment complex on West Swallow Road called The Gables at Silverplume. The police report says the couple had been drinking during a date and started arguing while in downtown Fort Collins.

They continued fighting inside the woman’s apartment.

Candice Sanchez, a neighbor and student at Colorado State University, woke up to police knocking on her door. She says police told her the woman in the unit next to her smashed a beer bottle over the victim’s head and stabbed him in the neck.

“I just was really shocked,” Sanchez said.

Neighbors say after he was stabbed Cassidy crawled down the stairs and across the sidewalk before collapsing. They said there was lots of his blood on the stairs of the complex. Sanchez said there were evidence markers right next to where she locks up her bike.

Mary Kate Francis, another neighbor, said she thinks the woman did the act in self defense.

“She was really defending herself and I think she has every right to be defended underneath it,” she said.

The woman is currently free on bond. She faces possible charges of domestic violence and second degree assault.

apartment Make My Day Law Might Apply In Stabbing Case

An image of the apartment where the stabbing happened (credit: CBS)