While this book seeks to move past anecdotes and rhetoric by relying, whenever possible, on data and large-scale statistical analysis, it is important not to lose sight of the awesome deprivation of liberty suffered by the people reflected in that data. People incarcerated in prisons and jails are subject to a host of harms, including physical injuries inflicted by guards and other inmates. Many facilities offer poor access to medical care, and the cramped setting creates fertile ground for the spread of illness. One study of the health impacts of New York prisons found “a 2-year decline in life expectancy for each year served in prison.”1