On November 19, 2018, a mass shooting took place at the Mercy Hospital and Medical Center in Chicago, Illinois.

[5] Police told the media that a confrontation in the parking lot between an emergency room doctor and her ex-fiancé escalated.

An eyewitness claimed that O'Neal ran over to the group for help, and was on her phone attempting to call 9-1-1, and told them that the gunman would kill her.

[12] Lopez had a valid FOID (Firearm Owners Identification) card and a concealed carry gun permit.

[16] The hashtag #ThisIsOurLane was seen on social media after the shooting with multiple medical professionals rallying for support for those in the hospital, and some echoed anti-gun sentiments as well.