As psychology is a science of behavior and complex mental processes it can be utilized in various ways to investigate the crime and provide justice. The perpetrators of crime use many tricks to conceal their crime. Some may resort to faking mental illnesses to escape prosecution while others may feign dumbness or deafness to avoid questioning by law enforcement authorities. It is prudent, therefore, that the criminal justice systems utilize psychology and its methods to understand criminal behavior through conducting screenings and assessments on accused persons and prisoners, to investigate psychological disorders among criminal or civil court defendants, and to examine the mental state of criminals to consider if they can stand before a magistrate or jury. Psychologists, and other mental health professionals such as psychiatrists, therefore, have a wide range of roles to play in the proper administration of justice.
Both Psychology and Law seek to control human behavior for the good of the individual concerned, the community they live in as well as the country they are a citizen to. Psychology seeks to control behavior through altering cognition or thought processes by getting rid of „bad‟ thoughts and replacing them with „good‟ thoughts while law controls human behavior by imposing sanctions such as punishment on the offender for them to feel the pain and shun bad behavior. The two fields, therefore, play a complementary role in controlling human behavior for the good of society.
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