After three previous murder trials ended with a deadlocked jury, former Tulsa police officer Shannon Kepler was convicted last month of first degree manslaughter in the shooting death of his daughter's 19-year-old boyfriend. Now, he has been formally sentenced in the case, with Tulsa County District Judge Sharon Holmes upholding the jury's recommendation of 15 years in prison.

The case began in 2014 after Shannon Kepler and his wife Gina, also a Tulsa police officer, dropped their 18-year-old daughter Lisa off at a local homeless shelter. The Keplers had been having difficulty with Lisa, whom they had adopted when she was 6 years old, and took her to the shelter in a "tough love" move.

While at the shelter, Lisa met 19-year-old Jeremy Lake, whom she said came to the shelter to volunteer. Lake took her under his wing and brought her to live with him and his aunt. After they announced their new relationship on Facebook, Shannon Kepler became concerned about his daughter's whereabouts and went looking for her near the shelter.

On August 5, 2014, the Tulsa police officer pulled up beside his daughter and Lake as they walked down the street. The three exchanged angry words, and Kepler pulled out a gun and shot Lake before driving away.

Kepler was charged with first degree murder, and his wife Gina was charged as an accessory after the fact.

The defendant continued to argue that he shot Lake in self defense, maintaining that Lake pulled a gun on him first. However, no witnesses were able to verify that Lake indeed had a gun, and no weapon was found at the scene. Lake's family testified that the young man was reaching for a handshake, not pointing a gun.

Kepler was tried for murder three times, but each time, the jury deadlocked. At the most recent trial, the jury was allowed to consider the lesser offense of first degree manslaughter.

After sentencing, Kepler did not speak, except to tell the judge he wanted immediate transportation to the Oklahoma Department of Corrections.