Kristopher Guenther, 32, testified Wednesday that his relationship with Lacey Jones-McKnight became rocky after he started talking about suicide and admitted to seeing another girl.
Guenther testified the night Lacey died in October 2012, they got into an argument and he tried to subdue her.
After she spit at him, he put her in a choke hold and they both fell backward, with Lacey losing consciousness.
Guenther testified he didn’t notice until after that she had turned blue.
He said he panicked and thought about taking her to hospital and then wrapped her in a blanket, but she was already dead.
Jones-McKnight’s body was found in Guenther’s car after he attempted suicide by trying to hang himself from an overpass.
Other witnesses have testified he drove across the city with her body, even showing it to a former girlfriend and admitting to Lacey’s mother that he had killed her daughter.
ALSO ON HUFFPOST: