A jury has started deliberations in the case of a Utah doctor accused of killing his cancer researcher ex-wife amid a bitter 2011 custody dispute.

Lawyers made closing arguments Thursday in the trial of Salt Lake City pediatrician John Brickman Wall.

The monthlong trial included blood-splatter demonstrations, heated exchanges over evidence and the testimony of a 21-year-old man who believes his father killed his mother.

Prosecutors allege the 51-year-old Wall attacked his ex-wife with a knife, drugged her with an anti-anxiety medication and drowned in her bathtub.

His lawyers say that theory is unbelievable, and it's more likely 49-year-old Uta von Schwedler killed herself.

Her death initially was treated as a suicide, but family and friends pushed for more investigation. Wall was arrested more than a year later.