Police brutality is the use of excessive or unnecessary force towards a civilian by the police force or a police officer. It also can be defined as the willful infliction of pain or suffering to an individual, that violates a civilians civil rights . Police brutality is evident throughout history and present is today, it is a social issue effected by discrimination and racism.
Police brutality and Racism in the U.S.
Forms of Police Brutality
Police are allowed to use force to secure an arrest, however, once they use excessive force it is considered as assault and brutality. Excessive force in policing includes force that is disproportionate to the situation, inflicting harm and injury on a civilian. Police officers must use their own judgement to determine the line between excessive force and force. Police brutality is often thought of as physical where excessive forced is used on people to comply with orders to intimidate or intentionally hurt civilians. Police officers use nerve gas, batons, pepper spray, tasers and guns. Brutality can also include psychological abuse, false arrests, verbal abuse, psychological intimidation, sexual abuse, police corruption, racial profiling, and political repression. 
Racial discrimination is unfair or prejudicial treatment of someone or a group of people on the grounds of their race. Racial discrepancies in policing are found in shootings and brutality related to racial profiling and discrimination. Most common form of recorded brutality in policing are related to violence including shootings and physical assault. People of colour and minority groups, specifically black people in the U.S. are found to be more likely to be shot at by police than people who are caucasian. Racial inequalities can also be found in police killings on unarmed victims are more likely to be minorities.
Police brutality has been found to be associated to racial profiling, and has become a issue of national significance. Differentiation in race, religion, politics, or socioeconomic status can affect police forces to racially profile individuals, causing more police traffic stops, search, field interrogations and arrest practices.
According to race conflict theory, discrimination is a necessary social process. Society is shaped by competing interests in different social groups, who compete for dominance to maintain social structure that benefit their own group. Conflict theory argues that the power of the dominate social group gets to control social order. This dominate group control law making and law enforcement, therefore, "laws are made to serve the interest of the privilege and the police are used to suppress and control any blemishes of a society that threatens the status quo". These laws and enforcement are used in dominate groups in society to minimize threats made by others they label as dangerous, which is the minority groups and the poor. Racial minorities are considered a threat to the ruling class, therefore, it reflects the handling of situations made by police officers, contributing to racial profiling and biases. Conflict theory asserts that the dominant social class, like police enforce social control and view minorities as a risk for criminality.
The article by Petrocelli (2013) found evidence of racial profiling where minorities were stopped more frequently than whites, blacks were 23% more likely to be stopped and hispanics 39% more likely to be stopped. 
In the Boston University School of Medicine study, they found higher racial differences in police shootings on unarmed victims in areas where residential segregation occurs. This evidence shows that higher rates of fatal police shootings between police officers and black suspects are not just a result of interactions, but rather there is a different response based on the race of a civilian. This is a result of structural racism in society that reflects police force. Researchers in this study found the association between increased racial segregation and brutality. The more a state in the U.S. has evidence of racial segregation, the higher increase in police shootings of unarmed black victims, compared to unarmed white victims. 
Racial biases in law enforcement has been in the attention of the public eye recently. Researchers has brought up implicit racial biases at a unconscious level in police officers. These implicit biases come from unconscious and unintentional beliefs, where stereotypes and attitudes influence beliefs, actions and decisions of individuals. People who hold these biases are unaware of them and don't express these beliefs explicitly- verbally to themselves or others. An example of this type of impact bias includes the unconscious association between people of colour and crime.
In a study by Joshua Corell, at the University of Colorado, they explored implicit biases to race in a laboratory study. They developed and tested "the police officer's dilemma", using a first-person-shooter game. Participants goals are to shoot armed target but not unarmed targets when presented with images of young men who are either white or black, and holding items like guns or neutral objects like soda cans and cellphones. The results suggest an implicit bias, where participants shoot armed targets more often and faster when the images were of black individuals, rather than white. They also found that participants did not shoot as often and quickly when target was white. This is evident in the police force where officers are found to react faster to black targets, than white targets, therefore, evidence of targets associated with racial stereotypes.
History on Slavery
Slavery has been a long time practice throughout history and contributes to the discrimination that occurs today. Slavery has been practiced in American colonies since the 17th and 18th century. Slaves were brought to America from Africa to produce crops such as tobacco and cotton. The impact of slavery has influenced American history and in the modern world.
Racial discrimination is a product of the African slave trade stemming from capitalism. Racial categories started to become embedded into society when slavery was established. Slavery emphasized groups based on inherited characteristics such as skin colour, to make one group more superior than another.
Incidence and Prevalence
High Profile Cases
There are many high profile cases recently related to police shootings and deaths of black civilians that have caused public scrutiny. The following is a list of a few that has made major headlines.
- Michael Brown: In August 2014, Brown was unarmed and fatally shot by a police officer. He was 18 years old at the time, and this incident caused months of protest and the Black Lives Matter movement was created after public attention. 
- Philando Castile: Castille was shot and killed in July 2016 in Minnesota while pulled over in his vehicle. At the time, his girlfriend and young daughter was in the car. According to Castile's girlfriend, Castile was reaching to get his ID card and the officer pulled out his gun and shot him. The officer has been charged with manslaughter.
- Tamir Rice: The 12 year old was shot and killed in Cleveland in November 2014. The boy was reported to have been waving a gun around, however it was a pellet gun the young boy was playing with. The officer fired his gun moments after arriving on scene and getting out of the police car.
- Jamar Clark: Clark was shot dead in November 2015, in Minneapolis. According to some witnesses, Clark was handcuffed when he was shot in the head. However, they concluded in court that Clark tried to reach for the officers weapon. This case caused weeks of protest and backlash to the public.
The statistics relating to police brutality and race is quite shocking in America. According to Mapping Police Violence, in 2015 they found that black people are 3 times more likely to be killed by police compared to white people, and out of the people killed by police 30% of black victims were unarmed. They also found that 1 in 3 black people killed by police in 2014 were suspected of a violent crime and allegedly armed. This means that 2 out of 3 of them were killed innocent. Despite the injustice found in fatalities in black individuals, police were not accounted for their cruel actions. Mapping Police Violence found that 99% of cases in 2015 the officers were not convicted of any crimes relating to deaths of individuals.
Furthermore, they found an association between brutality and state individuals live in. Police killings towards black people were 7 times more likely in Oklahoma compared to Georgia. This difference could be due to racial disparities in the populations of the states. Ratio between whites and blacks in the two states have a striking difference. According to United States Census the white population in Oklahoma is 75%, while black populations is around 8%. In Georgia, the whites make up around 61% and blacks 32%.  More police killings of blacks in Oklahoma could be due to the ratio of racial differences, blacks in the state are a minority group, while whites are the dominant group. In respects to conflict race theory, this could be due to racial minorities posing a danger to the privileged group (whites). The majority group views the minority as criminals, thus leading to a higher likelihood of being killed in a police encounter. Perhaps we don't see as much brutality in Georgia due to the larger population of blacks, and there is a smaller gap between whites and blacks, where the groups are more balanced, leading to less racial profiling and discrimination.
High profile cases relating to excessive force in police has been transcribed through society through mass media and has caught scrutiny in the public. In response to incidents of police brutality, the public has responded with protested and created movements towards justice.
Black Lives Matter Movement
The Black Lives Matter movement started in 2013 on twitter when a hashtag went viral with #BlackLivesMatter after the acquittal of a police officer in a fatal shooting on Trayvon Martin. The movement is now a international activist movement campaigning on structural racism and violence towards black people. Their goal is to create a "world free of anti-blackness, where every black person has the social, economic, and political power to thrive. Black Lives Matter has become a large connecting network in helping communities bring awareness to state-sanctioned violence and anti-blackness. This group acts together to bring justice in violence in black communities by the state and vigilantes. Also, they are working towards a world where black people are no longer a target for discrimination, emphasizing justice, liberation and peace with one another.
Blue Lives Matter and All Lives Matter Movement
The Blue Lives Matter movement was made in response to the Black Lives Matter by critics against the movement. The activist movement brings awareness to killings of police officers. It is a network to support police officers and state workers to prevent violence against them. As a result of this movement Louisiana legislation is the first state to pass a bill to protect police officers under hate-crime laws. Criticism has been raised on the movement because hate-crime laws based on an occupation does not seem as serious compared to race, religion or sexual orientation.
Another movement called All Lives Matter is another response to the Black Lives Matter movement, where they believe in equality amongst all people. They argue that not only black lives matter but all other races matter too. However, critics say that this movement does not acknowledge inequality in the system. It does not highlight how people are discriminated based on race. Smith's (2017) article, describes it as more evidence for injustice. He argues that it tries to reduce racism and prejudices against African-Americans, where white people don't "see race".
- Body cams: police and citizens would try to abide to laws since they know they are being watched and everything is being recorded. Also, it can help solve cases and charge officers and criminals easier with video footage.
- Awareness campaigns in racism like the Black Lives Matter Movement.
- Try to counter traditional stereotypes and eliminate implicit biases. Studies show that you can prime participants to consider multicultural attitudes.
- Creating protocols and checklists for law-enforcement situations where violence is the last option.
- Police officers getting to know their communities and gain trust with civilians. 
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