Los Angeles prosecutor: CHP officer's roadside beating of woman 'was legal and necessary'
CHP officer Daniel Andrew is filmed pummeling Marlene Pinnock on July 1, 2014. (KNBC-TV)

California Highway Patrol officer Daniel Andrew, who was caught on film beating 51-year-old Darlene Pinnock last July, will not face criminal charges, the Los Angeles Times reported.

"When looking at all of the evidence, and especially the medical reports and eyewitness accounts, it becomes exceedingly clear that the officer, who was alone and struggling with Ms. Pinnock precariously close to evening freeway traffic, acted within the law," county District Attorney Jackie Lacey said in a statement. "In our analysis, his use of force was legal and necessary to protect not only his own life but also that of Ms. Pinnock."

Andrew came under criticism after a motorist videotaped him taking Pinnock to the ground near Interstate 10 before repeatedly hitting her on the head.

Pinnock was subsequently hospitalized, while Andrew was accused of falsifying medical records to omit his actions in a lawsuit filed by her family. The officer stepped down from his job on Tuesday under the terms of a $1.5 million settlement

However, local activists like Najee Ali demanded that Lacey's office press charges against Andrew, and accused her of purposefully announcing her decision a day after a fatal shooting attack in nearby San Bernardino.

"The whole nation’s eyes are on the tragedy in San Bernardino," Ali said. "The fact she [Lacey] slid this in, the timing is very suspect and it demonstrates cowardice."