David Kalac

"Turns out, it's way harder to strangle someone to death than it looks on the movies.."

David Michael Kalac, a.k.a. "The 4chan Killer", is an American murderer who killed his girlfriend and posted pictures of her body on the infamous imageboard website, 4chan.

History
Before murdering his girlfriend, Kalac had already problems with police, including domestic violence and aggravated assault. On November 4, 2014, Kalac visited a bar and drank beer and vodka for four hours. For unspecified reasons, Kalac killed his girlfriend, Amber Coplin, after returning home and posted photos of her nude body online. Her body was found one hour later by her 13-year-old son. Using his girlfriend's car to escape, Kalac fled from his house and called 911. Investigators were able to trace his cellphone, which resulted in Kalac messaging two of his friends, saying that they would see him in the news. 19 hours later, Coplin's car was spotted and police pursued the car, however, Kalac managed to escape by swerving into oncoming traffic.

Hours later, about 20 miles southwest of Portland, Kalac surrendered and was arrested. Kalac was subsequently convicted of second-degree murder, later first-degree murder. Inside Coplin's bedroom, police found messages written by Kalac, such as "she killed me first" on a picture and "dead" on a driving license, which was left near her head. Kalac's motive for killing Coplin is currently unknown, though he mentioned the fact that he was drunk when it happened, and alleged that she had made him angry, other sources say that Coplin had a romantic relationship with another man, and Kalac found out about it.

Modus Operandi
"I just wanted to share the pics before they find me."

When killing Coplin, Coplin manually strangled, then switched to ligature strangulation with a shoelace. While strangling her, Kalac also bludgeoned her in the head with an unspecified object, which was her cause of death, alongside the ligature strangulation. Afterwards, Kalac removed her clothing and took pictures of her body before posting them online. Along with the pictures, Kalac also claimed that he would taunt police into shooting him.

Known Victims
"I killed Amber Coplin. I strangled her with my hands, then a shoelace. I had no reason other than i was drunk and she pissed me off. Running from the cops was so fun."
 * November 4, 2014: Amber Lynn Coplin, 30

On Criminal Minds
Kalac's act of posting images of his girlfriend after killing her, accompanied with taunting messages, seems to be almost identifical to William Pratt's M.O., who appeared on the episode Hashtag, which aired a week after the murder occured.