In 1971, social psychologist Philip Zimbardo conducted the Stanford Prison Experiment, a two-week, grant-funded mock prison experiment at Stanford University. His work became the stuff of legend when it was called off after six short days due to the brutality of the student "guards" and the emotional trauma suffered by the student "inmates." Zimbardo concluded that "most of us can undergo significant character transformations when we are caught up in the crucible of social forces."

Thirty years later, Zimbardo again rose to national attention when he testified for the defense in the court martial of Sgt. Ivan Frederick, a guard at Abu Ghraib prison, arguing for a reduced sentence due to the influence of poor prison and military management on the situation. (For the record, at that trial, Sgt. Frederick received the maximum eight-year sentence permitted under law.)

Zimbardo's new book, The Lucifer Effect, capstones his four-decade career studying what makes good people do bad things, from the Stanford Prison Experiment to the Abu Ghraib atrocities to lessons from history. Zimbardo wants to know how moral people can be seduced to act immorally -- what the incentives for crossing the line between good and evil might be. The first 200 pages are a detailed account of the six days of the experiment, followed by a section with reflections and insights on the experiment and its outcome. The book concludes with another 200-page section on modern applications of the Stanford Prison Experiment and lessons from history -- namely, Abu Ghraib.

The scholar makes a compelling argument for holding the military and government accountable for creating the environment that propelled ordinary soldiers into sadists. In this expose of human nature, the author proves how vulnerable we all are to the powerful effects of our Situation as well as the System.

Zimbardo's 1970s experiment was not without its detractors. The experiment itself is shocking in modern times -- no school or researcher would subject themselves to the litigation that could result from such a research setting. Zimbardo himself was a part of the prison setting, instead of a neutral observer, so the conclusions are subjective and unrepeatable. Critics also cited a lack of scientific controls, an environment of "role playing" to the observer's standards, and the small sample size and extremely short duration of the study. Given that it can't be repeated for social and legal reasons, we are left with only this small, imperfect slice of data about his study. In many ways, The Lucifer Effect shows exactly how relevant the Stanford Prison Experiment was, because Zimbardo is able to place it in the larger context of both historical examples and of our modern war.