Sen. Holly Mitchell sits at her desk on the fifth floor of the Capitol and holds up a book.

On the cover a small boy in oversized jeans and a Tommy Hilfiger T-shirt stands on a plastic milk crate, too small to reach, as a police officer presses the young child’s ink-soaked fingertips onto a piece of paper.

“That image just stuck with me,” Mitchell said.

The senator from Los Angeles is pushing a bill through the Legislature that would bar the state from prosecuting children under age 12.

In 2015, 874 cases involving children under 12 were referred to California juvenile court for crimes such as curfew violation, truancy, vandalism, theft, trespassing, assault and battery and robbery, according to a UCLA analysis of state justice department data.

Mitchell believes it makes more sense to attempt to understand the source of the child’s problems that led up to the crime and use social services to help them. In lieu of doing time in a jail cell at juvenile hall, children would be redirected to dependency court, child protective services, mental health counseling and other services at the local level.

Senate Bill 439, set for its first hearing in the Senate Public Safety committee on Tuesday, is sponsored by the Children’s Defense Fund and other juvenile justice organizations.