In elementary school, Benita Veliz dreaded substitute teachers. Her classmates would act up and the sub would threaten to call the principal, a prospect so upsetting to Veliz that her regular teacher began placing her in a colleague’s classroom on days the teacher could not make it to class. Imagine how Veliz, now 23, reacted this January when she was thrown in jail after a traffic stop because she is an unauthorized immigrant. “To go from that to being in jail was surreal,” Veliz said, tears welling in her eyes. Veliz’s parents brought her across the border when she was...