An attorney for Drew Peterson, a former Chicago-area police sergeant accused of killing his ex-wife, said Tuesday the prosecution failed to even prove a murder took place.
Prosecutors said that common sense would lead a jury to a guilty verdict.
Peterson's fate will be deliberated beginning Wednesday morning, after the attorneys in the case that has attracted nationwide attention wrapped up their closing arguments.
Peterson, 58, is charged with murder in the death of Kathleen Savio, his third wife, who was found dead in her dry, clean bathtub March 1, 2004.
Prosecutor Chris Koch called on the jurors to use their own experiences in life when determining guilt or innocence.
"I ask you to keep in mind common sense, common sense. Because it is clear that this man murdered Kathleen Savio," Koch said.
Peterson has pleaded not guilty to two charges of first degree murder, one by intentionally killing her and the other by engaging in behavior that led to her death.
The defense contends Savio fell accidentally, hit her head and drowned.
Defense attorney Joe Lopez said that 300 people each year die in bathtub mishaps.
"People slip and have household accidents all the time ... at least 1.6 people out of a million die in the bathtub," he said. "And she was the one. And they want to make it a murder."
Koch said in closing that the evidence pointed to murder.
"We have left-front injuries, left-side injuries, left-back injuries, right injuries, right and left injuries. So it's not just one side of her body; it's multiple sides, four sides. How can you get that in one fall? You can't. You can't do it. It's not possible," Koch said.
Lopez countered by saying the prosecution failed to prove its case.
"The framers of the Constitution would barf at this evidence," he told the jury. "There's nothing but doubt in this case. People get on the TV and lie, just like they do in this courtroom. ... People lie when it's for their own agenda."
After court adjourned for the day, Lopez told reporters: "They haven't even proved a homicide took place."
The case did not arise until after Peterson's fourth wife, Stacy, went missing in October 2007. It was during the search for Stacy Peterson, who has not been found, that investigators said they would look again at Savio's death, which was initially ruled a drowning.
Savio's death was ruled a homicide in February 2008, and Peterson was later arrested and indicted on first-degree murder.
Peterson was married to Savio in 2001 when he had an affair with then-17-year-old Stacy Cales, who later became his fourth wife. Savio and Peterson filed for divorce in October 2001 and their relationship remained contentious for the next several years.
Bolingbrook police records indicate officers were called to Savio's home 18 times to intervene in domestic fights from 2002 to 2004. Peterson had Savio arrested twice for domestic violence, though she was found not guilty in both cases.
On February 27, 2004, Peterson picked up his two sons from Savio's home and spent the next two days with them. Prosecutors believe he entered her home again early on February 29 and killed her.
At the time of her death, which authorities initially treated as an accident, a court was mulling how the couple's marital assets would be divided, and Savio was set to receive part of Peterson's pension and other support.
The monthlong trial has been marked by repeated missteps by the prosecution that have angered Judge Edward Burmila and the defense.
At least four times since the trial began, prosecutors have allowed witnesses to testify to details Burmila has told them not to go into -- such as whether Savio had a protective order against her husband or allowing a witness to demonstrate climbing into a bathtub.
In some cases the defense has sought a mistrial and in others they have asked the judge to strike entire testimony. Burmila has instead ordered the jury to disregard elements of the testimony that went against his orders.
"The disrespect to the court is shocking," Burmila told the prosecution last week.