Aubrey Trail, 52, screamed “Bailey is innocent and I curse you all,” seconds before slashing his own throat in front of a courtroom in Wilber, Nebraska, US, on Monday.
Ms Loofe vanished on November 15, 2017, after gushing to a friend about a future second date with Boswell, whom she described as her “dream girl.”
Both Trail and Bailey deny killing the 24-year-old and claim she died during an orgy gone wrong.
They claim the 24-year-old was choked during the group sex session which led to her death.
Ms Loofe’s body was cut up into 14 separate pieces and scattered throughout Saline County in Nebraska.
Police were able to identify the recovered body because of the victim’s distinctive arm tattoo which read: “Everything will be wonderful someday.”
Medial examiners later discovered the woman’s tongue and lung’s had been cut out during the evil act.
Trail’s “accomplice” is girlfriend Bailey Boswell, who is also on trial for the first-degree murder of Sydney Loofe, 24, in November 2017.
In the horror footage of the incident, Trail collapses to the floor out of his wheelchair after cutting his throat with the unidentified weapon.
He appears to be unconscious after the ordeal and was soon rushed to a hospital.
According to reports he was released from hospital after receiving stitches but wasn’t in court when the hearing resumed on Tuesday.
Trail’s self-harm comes weeks after the son of a murdered woman lunged at her suspected murderer.