An independent investigation said officers were not clearly identified when they shouted obscenities and honked the horn in their unmarked vehicle in an attempt to clear a street blocked by partiers. A wild fight ensued between officers and the crowd.
Five people were arrested, which drew community demonstrations claiming racial bias and police brutality.
The report heavily criticized police for issuing a false report to the media, claiming that officers wore police badges and weapons. It also stated that someone in the crowd feigned pulling a gun and that an officer was hit with a bottle.
Police Chief Darren Pytel has apologized for police actions during the incident.
The so-called "Picnic Day 5" reached a settlement after being arrested and were placed on one year’s probation. Two officers were disciplined following the incident.
This year’s Picnic Day, a heavily attended open house for UC Davis, will be held on April 21. Police say this year all officers will be in uniform and drive well-marked police vehicles.