The Bonita Springs man, accused in the 2015 killing of his wife with two other men, was found guilty as charged by a Lee County Jury on Wednesday.
Mark Sievers, 51, was convicted of first-degree murder and conspiracy to commit murder after jurors deliberated for about four hours.
His wife, Teresa Sievers, 46, was found bludgeoned to death on the kitchen floor of her family's home on Jarvis Road in Bonita Springs on June 29, 2015.
The trial for Mark Sievers will now move into a penalty phase, where it will be determined if Mark Sievers is sentenced to death.
Jurors will return to the Lee County Justice Center at 8:30 a.m. Tuesday for the next portion of the trial.
Members of Teresa Sievers' family, including her mother and siblings, sat in the second row of the gallery behind the prosecution table for the verdict reading.
A large group of Teresa Sievers' family and friends, some who testified in the trial, began crying and embraced each other with hugs after jurors left the courtroom.
"We are obviously very happy with the verdict," Teresa Sievers' brother Patrick Tottenham said as he walked out of the courtroom and into an elevator to leave the building.
Teresa Sievers' sister Ann Lisa said she was relieved and felt justice had been served.
"It's been a long time," Lisa said through tears. "I just can't wait to put it behind and start living my life. I'm just so glad it's over. We just want to get on with our lives now."
Mark Sievers did not react when the verdict was read, and he appeared he may have been in shock while the judge discussed scheduling for the next portion of the trial.
Defense attorneys Michael Mummert and Gregory Messore did not comment on the verdict.
During the next phase of the trial, prosecutors will have to prove beyond a reasonable doubt that at least one aggravating factor applies to Mark Sievers to make him eligible for the death penalty.
"We are pleased with the jury's verdict," said Assistant State Attorney Cynthia Ross as she left the courtroom. "But this is only the first stage and there is the second phase that is coming next week so it's time for us to get back to work."
Florida Statute outlines 16 aggravating factors, including some related to the defendant's criminal history and the age and person of the victim.
If the offense was committed for "pecuniary gain" that is also considered an aggravating factor, per Florida Statue.
During the guilt phase of the trial, prosecutors claimed Mark Sievers planned his wife's murder with the help from his best friend Curtis Wayne Wright Jr.
Prosecutors alleged Mark Sievers was motivated in part by the large life insurance policies on Teresa Sievers at the time of her death and said Wright enlisted Jimmy Rodgers to help with the murder.
Both of Mark Sievers' co-defendants in the case are awaiting sentencing. Rodgers was convicted by a Lee County jury of second-degree murder on Oct. 23 after about a monthlong trial.
Wright pleaded guilty to second-degree murder in 2016 in exchange for a 25-year prison sentence. He testified on behalf of the prosecution in the Rodgers trial and the Mark Sievers trial.
In the next portion of the trial, all the jurors must agree that prosecutors proved at least one aggravating factor applies to the defendant then the defense will get to present mitigating circumstances.
The defense will be allowed to present anything relating to Mark Sievers' background, mental health, character or record that would give the jury a reason to spare his life or that could persuade the jury that life without parole is enough.
After the evidence is presented, the jury must vote unanimously to impose the death sentence to move forward. Then the final decision during a death penalty trial in Florida comes from the judge.
The trial is being presided over by Lee Circuit Judge Bruce Kyle.