This week we are covering the Science special issue on mass incarceration. Can a dog find a body? Sometimes. Can a dog indicate a body was in a spot a few months ago, even though it’s not there now? 

There’s not much scientific evidence to back up such claims. But in the United States, people are being sent to prison based on this type of evidence. Host Sarah Crespi talks with Peter Andrey Smith, a reporter and researcher based in Maine, about the science—or lack thereof—behind dog-sniff evidence.

With 2 million people in jail or prison in the United States, it has become incredibly common to have a close relative behind bars. Sarah talks with Hedwig Lee, a sociologist at Washington University in St. Louis, about the consequences of mass incarceration for families of the incarcerated, from economic to social.