Law is the most important system that we have to maintain our complex societies-laws protect our property, safety, health, economy, and natural environment. But why do some radically change behavior whereas others are routinely broken? Drawing upon decades of research, professors Benjamin van Rooij and Adam Fine reveal the behavioral code: the root causes and hidden forces that drive human behavior and our responses to society's laws. Using compelling examples-from park rangers in Arizona who reduced theft by altering "No Stealing" signs to why a $2.3 billion legal settlement failed to reduce corporate malfeasance at Pfizer-they argue that law is destined to fail if it continues to rely on our intuitions rather than behavioral science. Van Rooij and Fine unveil a fundamentally new approach to law, a behavioral jurisprudence that delivers the safety and justice our society so direly needs. Book jacket.