The trial for a man charged with first-degree manslaughter ended with the man taking a plea deal after the jury could not reach a unanimous verdict. 

Justin Henley, 21, is accused of killing Sac and Fox police officer Nathan Graves in a head-on collision in Lincoln County.

Henley pleaded guilty to second-degree manslaughter. 

After several hours Friday, the jury could not reach a unanimous verdict and Henley voluntarily made a plea. 

The prosecution recommended two years in prison and a $100 fine. 

The trial for Henley started on Monday, after waiting more than two years for his day in court. 

Back on Jan. 24, 2017, investigators said Henley crashed head-on into Graves's vehicle after they said he passed a vehicle in a “no passing zone.” Graves died on scene. 

Due to Grave’s death, Henley was charged with first-degree manslaughter. 

“It’s State Highway 99, north of Stroud. It’s a section of road that has some hills. There are passing zones and no passing zones. But in many of the places the passing zones or the no passing zones, the lines are very faded. At some points it’s even non-existent. It’s important to remember that this happened at 5:50 in the morning in January. It’s dark out,” said defense attorney John Hunsucker. 

For the majority of the day, both sides focused on the stripping in the roadway on that stretch of State Highway 99. Whether it played a role the morning of the crash. 

Henley also claimed on the stand that he thought it was a passing zone when he and another white truck passed a slower vehicle on State Highway 99. 

Both the state and defense gave lengthy closing arguments.

The defense claims that he believes the maximum, manslaughter in the first degree, is due to an officer being involved.

Both sides left the jury with a plethora of information. 

The sentencing hearing has been set for July 25.