Law and Neuroscience in the United States

Neuroscientific evidence is increasingly reaching United States courtrooms in a number of legal contexts. Just in calendar year 2010, the U.S. legal system saw its first evidentiary hearing in federal court on the admissibility of functional magnetic resonance imaging (fMRI) lie-detection evidence; the first admission of quantitative electroencephalography (qEEG) evidence contributing in part to a reduced sentence in a homicide case; and a U.S. Supreme Court ruling explicitly citing brain development research. Additional indicators suggest rapid growth. The number of cases in the U.S. involving neuroscientific evidence doubled from 2006 to 2009. And since 2000, the number of English-language law review articles including some mention of neuroscience has increased fourfold. In 2008 and again in 2009, more than 200 published scholarly works mentioned neuroscience. The data clearly suggest that there is growing interest on the part of law professors, and growing demand on the part of law reviews, for scholarship on law and the brain (Shen 2010). In addition, a number of symposia on law and neuroscience have been held in the United States over the past few years, and despite the notable youth of the field, courses in Law and Neuroscience have been taught at a number of U.S. law schools. This vivid interest in neurolaw, from both scholars and practitioners, is born of the technological developments that allow noninvasive detection of brain activities. But despite the rapid increase of legal interest in neuroscientific evidence, it remains unclear how the U.S. legal system – at the courtroom, regulatory, and policy levels – will resolve the many challenges that new neuroscience applications raise. The emerging field of law and neuroscience is being built on a foundation joining: (a) rapidly developing technologies and techniques of neuroscience; (b) quickly expanding legal scholarship on implications of neuroscience; and (c) (more recently) neuroscientific research designed specifically to explore legally relevant topics. With the institutional support of many of the country’s top research universities, as well as the support of the John D. and Catherine T. MacArthur Foundation, among other private foundations and public funding agencies, the U.S. is well positioned to continue contributing to international developments in neurolaw. This chapter provides an overview of notable neurolaw developments in the United States. The chapter proceeds in six parts. Section 1 introduces the development of law and neuroscience in the United States. Section 2 then considers several of the evidentiary contexts in which neuroscience has been, and likely will be, introduced. Sections 3 and 4 discuss the implications of neuroscience for the criminal and civil systems, respectively. Section 5 reviews three special topics: lie detection, memory, and legal decision-making. Section 6 concludes with brief thoughts about the future of law and neuroscience in the United States. As judges, lawyers, legislators, and the public become more acquainted with neuroscientific evidence, and as neuroscience continues to produce more legally relevant findings, it is likely that we will see continued expansion of law and neuroscience in the United States.