Matthew B. Johnson’s general interest involves how psychology informs due process. His scholarship and research have focused on the areas of interrogation and confession, wrongful conviction, mental status defenses, and parental rights termination in family court. He recently developed an instrument to assess 'Interrogations Expectations', an aspect of the Miranda comprehension and waiver process that has been neglected in the research literature. Dr. Johnson's work in this area demonstrates that suspects may understand the Miranda rights but doubt the police will honor the rights during interrogation. During the Spring 2010 semester, Professor Johnson was Visiting Professor at Rutgers University, School of Criminal Justice, where he conducted a graduate seminar on 'Interrogation and Confession'.
Professor Johnson's publications and testimony have been cited favorably in New Jersey Supreme Court decisions. He served on the Executive Committee of New Jerseyans for Alternatives to the Death Penalty (NJADP.org), the lead organization in the successful campaign that abolished the death penalty in New Jersey in 2007. He also was a member of the American Bar Association, Section on Individual Rights and Responsibilities – Task Force on Mental Disability and the Death Penalty. In 2013 Professor Johnson was elected to the Board of the National Association of Black Psychologists and he authored the organization's Death Penalty Abolition Resolution (2012) and public policy paper on the death penalty (2013). Dr. Johnson was named the John Jay College of Criminal Justice Outstanding Teacher in 2007. Dr. Johnson is involved the teaching and training of psychology students at the undergraduate, masters, and doctoral level.