After providing varied explanations, together with that poisonous fumes induced her to suffocate, Madsen informed the court docket that Wall died on account of a buildup in stress inside his home-made UC3 Nautilus submarine.
Wall, 30, had disappeared in mid-August 2017 after boarding Madsen's submarine while researching a story.
Madsen has denied murder and said Wall died accidentally inside the submarine, but has confessed to throwing her body parts into the sea.
Think your friends would be interested? Today at 1pm local time (1100 GMT), a judge and two jurors will rule whether her death was an accident or a murder.
Defence lawyer Betina Hald Engmark attacked the lack of conclusive physical evidence in the case, with the coroner unable to determine either the cause or timing of death with accuracy. Madsen's lawyers say they will appeal the decision as soon as possible.
But many details of Wall's final night remain unclear and are likely to stay so unless Madsen chooses to share anything further.
A life sentence is the harshest penalty in Denmark and is normally reserved for people convicted of more than one murder.
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President Ronald Reagan called it a genocide in a 1981 speech about the Holocaust; no USA president since has called it genocide. Mills, the goal of the US remains that there be an "honest and true" reckoning of the facts and acknowledgment of the past.
But should Madsen receive a sentence of 16 years or less, Mr Buch-Jepsen argued that the defendant to be placed in forvaring, or safe custody - a sentence with no definite time limit.
Madsen's explanation that the journalist died accidentally from Carbon dioxide asphyxiation on board his submarine was corroborated as plausible by one expert witness, and dismissed by another, making it hard to prove either way.
Wall, a freelance reporter, had set off with the eccentric, self-titled "inventrepreneur" on his vessel on the evening of August 10 to interview him for a story.
The court heard how the injuries inflicted on Wall reflected the content of more than 40 violent video clips found on Madsen's laptop.
Fourteen stab wounds and piercings were also found in and around her genital area.
She said Madsen did not give "a trustworthy" explanation. Madsen simply stated that he was sorry for anything that had happened. Her boyfriend told the court that she was "incredibly ambitious" and "amazingly curious".
In all, Madsen was found guilty on all three charges: which were the indecent handling of a corpse, premeditated murder, and "sexual relations other than intercourse of a particularly risky nature".