Prosecutors said David Ditto brutally beat and then strangled his wife, Karina, in their Mira Mesa home on March 12, 2010. Ditto told authorities Karina fell down the stairs of their home and died from her injuries.San Diego Fire-Rescue Department paramedic Lisa Challendler said she's seen hundreds of victims of falls. But under questioning from Deputy District Attorney Claudine Ruiz, Challendler said what David Ditto told paramedics that night about how long it had been since his wife had fallen didn't add up."He said that she had been down for two minutes, and she didn't appear to me that she was down for two minutes. She appeared to have been down longer than that," Challendler said.Defense attorney Keith Rutman attempted to shoot down the timing issue."When people's perception of time changes based upon the thing that they're witnessing and undergo, right?" Rutman asked Challendler."Correct," Challendler replied."Including people whose loved ones have had horrendous accidents, yes?" asked Rutman."Yes," said Challendler.The prosecution contends the Dittos' marriage was falling apart and that Karina wanted out. By August 2010, Karina Ditto had decided she was going to leave her husband, and in November, the defendant took out a life insurance policy on his wife in case of accidental death, Ruiz said."The bruises on her body tells you this was no accident," the prosecutor told the jury on Monday. "This was murder."However, the defense said Karina Ditto's death was simply a terrible accident.Rutman said on Monday that he would prove precisely that to the jury."She died of a horrible accident," Rutman said in his opening statement Monday. "Falls kill people ... and a fall killed Karina Ditto."If Ditto is convicted, he could get 25 years to life in prison.