This article was published in partnership with The Marshall Project, a nonprofit news organization covering the U.S. criminal justice system. Sign up for their newsletters, and follow them on Instagram, TikTok, Reddit and Facebook. STOUGHTON, Mass. — The last known person to see Sandra Birchmore alive was a police officer. He stopped by her apartment days before the elementary school teacher’s aide, 23 years old and newly pregnant, was found dead in February 2021. The medical examiner later... Read this story