This research work examines police brutality and violation of human rights in Nigeria – causes and its implications. The objectives of the study is to establish some cases of police brutality in Nigeria; to investigate the causes of police brutality and violation of human rights in Nigeria; to ascertain the implications of police brutality in Nigeria and to recommend ways to prevent police violence in Nigeria. To be able to achieve these objectives, four research questions were raised, such as, are there testimonies and evidences of human rights violation in Nigeria by the police? What are the causes of police brutality and violation of human rights in Nigeria? What are the implications of police brutality in Nigeria? How can police brutality and violation of human rights be prevented in Nigeria? The study made use of descriptive analytical method to analyze data gotten from secondary source such as academic journals, Newspaper publications, Television documentaries, Internet, relevant textbooks etc. Albert Bandura Social learning theory was adopted in this research, which explains that police, violates people’s right with impunity because they watch as other officers who violate people’s rights are not well sanctioned. The research reveals that police brutality in Nigeria has led to loss of lives, torture of detainees and extortion of suspects. Some of the recommendations are; The Nigerian police commission should strictly investigate and sanction erring officers, there should be a proper police reform, men of the Nigerian police should be subjected to a thorough mental examination before engaging them to service etc.