Day four of the trial of Julian Hernandez saw more emotion from the stand as Officer David Nelson's former beat partner testified before the court.

Hernandez is charged with five felony counts, including second degree murder and evading an officer causing death. He's accused of fleeing Bakersfield Police Officer David Nelson after a traffic stop in 2015 and leading him on a high speed chase; the pursuit would end when Nelson was killed in a crash on Panorama Drive.

Ryan Clark, Nelson's former beat partner, said he went through the academy with Nelson and the two were close friends. Clark testified that he arrived at the scene of Nelson's crash and he "tried prying that door open but he couldn't get it open," saying through tears that he arrived too late.

In addition to the emotional testimony from Clark, the prosecution brought forward a member of the CHP accident investigation team, who spoke about the specifics of the crash. He testified that the investigation showed that Nelson likely took the fateful turn on Panorama Drive at roughly 69 miles per hour.

Hernandez' past behind the wheel was also mentioned, as a former BPD officer testified that Hernandez resisted arrest during a traffic stop in 2012.

Day three also saw similar emotional testimony. Day five is expected to resume on Tuesday at 9:30 a.m., and Judge Lau expects closing arguments to take place Wednesday or Thursday.