Jean Casella and James Ridgeway have published an interesting history of solitary confinement at Longreads (*). Established in late-18th-century America by jailers who saw it as "a kinder and more effective alternative to more viscerally cruel punishments," solitary grew increasingly popular in the antebellum reform era of the mid 19th century. But the practice attracted harsh criticism as its psychological effects became clear, and by the 20th century it was far less common. Its comeback began with the U.S. Penitentiary in Marion, Illinois, which opened in 1963, developed a "Long-Term Control Unit" where prisoners were held in isolation, and in 1983 became the country's first "supermax" prison, where solitary confinement is the norm.
As mass incarceration took off, so did the Marion approach to punishment. "Throughout the 1980s and 1990s," Casella and Ridgeway write, "the idea of units or whole prisons designed for 'total control' rapidly gained traction." Soon, most the country's prisons and jails had
developed a solitary confinement unit of some kind. In the five-year period from 1995 to 2000 alone, the number of individuals held in solitary increased by 40 percent, and by 2005—the most recent year for which figures are available—a U.S. Bureau of Justice Statistics census of state and federal prisoners found more than 81,622 people held in "restricted housing." The census figures do not include individuals in solitary confinement in juvenile facilities, immigrant detention centers, or local jails; if they did, the numbers would certainly be higher, likely exceeding one hundred thousand....
Far from a measure of last resort reserved for the "worst of the worst," as many proponents claim, solitary confinement has become a control strategy of first resort in most prisons and jails. Today, incarcerated people can be placed in complete isolation for months or years not only for violent acts but for possessing contraband—including excess quantities of pencils or postage stamps—testing positive for drug use, or using profanity. In New York, about 85 percent of the thirteen thousand terms in disciplinary segregation handed down each year are for nonviolent misbehavior. The system is arbitrary, largely unmonitored, and ripe for abuse; individuals have been sent to solitary for filing complaints about their treatment or for reporting rape or brutality by guards.
Sometimes solitary confinement represents a sort of institutionalized paranoia:
About half of the people held in California SHUs ["Secure Housing Units"] may have committed no offense at all; instead, they are held in solitary because of the gang "validation" process, in which anyone deemed an active gang member is sent to an initial six-year term in the SHU, which can be extended to decades. Gang validation can take place based in large part on anonymous accusations. Commonly, these anonymous charges come from validated individuals in the SHU, for whom the only hope for early release has been summarized as "parole, snitch, or die." People have also been suspected of gang membership simply by possessing the book The Art of War or making reference to prison activist George Jackson.
Read the whole thing here.
(* The website describes the article as both a "longread" and a "brief history," but I don't think you should blame the authors for that.)