One day in 2016, as Arnulfo Gonzalez waited at a warehouse to pick up cargo, he stared at the filth caked on the back door of his box truck. After a moment of contemplation, he ran his finger on it.

The Mexican immigrant once had ambitions to become an artist. He had earned a degree in the subject from East Los Angeles College and taught ceramics workshops in Bell Gardens. He took his wife on date nights to drawing classes, where they used each other as subjects.