CLEARWATER, Fla. — Opening statements happened Monday afternoon in the murder trial of John Jonchuck, who is accused of throwing his 5-year-old daughter off a St. Petersburg bridge in 2015.

The prosecution argued Jonchuck killed his daughter to punish his mom and her mom. Prosecutors acknowledge he did "off the wall" things before and after his child's death, but they argue he was not insane at the time of the murder.

In contrast, the defense painted Jonchuck as a man who suffered a mental breakdown -- arguing he loved his daughter more than anyone.

After the opening statements were finished, prosecutors' first witness, St. Petersburg Police Officer Williams Vickers, took the stand.

Jury selection concluded last week after several days of questioning in Judge Chris Helinger's Clearwater courtroom.

Nine men and seven women make up the 12-person jury plus 4 alternates.

Investigators say Jonchuck threw 5-year-old Phoebe Jonchuck off the bridge, and a police officer witnessed the crime.

Timeline: Four years after he threw his daughter off a bridge, John Jonchuck's murder trial begins 

Phoebe Jonchuck's body was later recovered in Tampa Bay.

If John Jonchuck, 29, is found guilty of murder, he could spend life in prison.

The defense will not argue that Jonchuck didn't do it -- but rather that he is not guilty by reason of insanity. If he’s found not guilty by reason of insanity, Jonchuck will likely spend the rest of his life in a state mental hospital.

Hundreds of juror candidates were questioned last week after the court sent out 1,200 summons. The judge excused people for a variety of reasons. Some could not accommodate a month-long trial while others expressed too much personal bias or emotion towards the case.

Read: Jury selection resumes in trial for man who threw his daughter off a bridge

On Friday, two people were quickly dismissed after the judge determined they knew people on the witness list. Second phase screening continued Friday with the lawyers doing most of the questioning.

CLICK HERE TO WATCH THE TRIAL LIVE

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