Friday, June 24, 2016

How Gender and Race Affect Police Interactions


Recently, police violence has become the focus of a lot of media attention. It has formed many protests and organizations around reducing police violence. Many of the organizations are specially focused on reducing violence toward blacks because it is a problem disproportionately effecting the black community. This post seeks to investigate some of these claims and understand the relationship between the violence each ethnic group experiences and their violence against police.

The following graphics come from a conversation about disparities between races when it comes to police killings. The discussion turned to the fact that only some disparities are thought of as problems of the system but others are generally thought to be acceptable. For example, blacks make up about 11% of the population, but 29% of the police killings. This disparity is largely seen as racism in the law enforcement and the overall justice system. Critics of this assumption usually point to the higher rates of crimes committed by blacks compared to whites and other races. However, the use of crime statistics from, what some believe is a racist institution is not a good method for explaining the differences in police kill rates.

Another group that is disproportionately killed, compared to their percentage of the population, is men.  Males make up a little less than half of the population (49.1%), but are 94.2% of the police killing victims. However, no one asserts the justice department to be sexist. The group discussing this matter largely agreed the reason for men to disproportionately be killed by police is because men most likely kill police more than women.

The follow graphic was created to compare the population, the proportion of people killed by police, and the number of police killed, broken down by gender. Men make up 94.2% of police killings, but also were responsible for 97.5% of police murders. This means while only half the population, men are 16 times more likely to be killed by police than compared to women. However, the killer of a police officer is 39 times more likely to be a man compared to a woman.

A similar graphic was created broken down by race (Note: http://killedbypolice.net/ did not use the method of classifying asians as the population data and FBI, so asians was included in "Other" for the people killed by police. Also the FBI defines hispanics as a subset of whites and not their own category so this is why hispanics are not represented in the "Killed Police" section). The chart below shows blacks are much more likely to be killed by police compared to their portion of the population, however while only being 29.5% of the people killed by police and 11% of the population, 43% of police officers are killed by blacks. 

Personally, I do not believe you can say that one race can be expected to be killed more because they kill police more. I believe, unlike gender, there are socio-economic differences between the groups that could lead to a greater likelihood of turning to crime because of lack of economic opportunity. Another factor is the populations are not perfectly comparable. Whites and asians households have fewer children than black and hispanics [3]. This leads to a lower ratio of old people to young people in the black and hispanics populations. Since the vast majority of people committing murders and/or being killed by police are young, populations with fewer old people will look like they commit more murders per capita.

Below is the R code used to generate the plots.


Sources
[1] http://killedbypolice.net/ (May 2, 2013)
[2] https://www.fbi.gov/about-us/cjis/ucr/leoka/2013/tables/table_44_leos_fk_race_and_sex_of_known_offender_2004-2013.xls (April 10, 2016)
[3] http://www.pewsocialtrends.org/2012/05/17/explaining-why-minority-births-now-outnumber-white-births/ (April 29, 2016)

ewl e2earh maeh armaly2'i fi rmehiiarm
mmîW Srn'eW ,mtehaded pbii e ¡idada Sehîie

CPu1s)

This text was recognized by the built-in Ocrad engine. A better transcription may be attained by right clicking on the selection and changing the OCR engine to "Tesseract" (under the "Language" menu). This message can be removed in the future by unchecking "OCR Disclaimer" (under the Options menu). More info: http://projectnaptha.com/ocrad


########################### R Code ################################ 

######### By Race ###########
# Cop killing graphic
# https://www.fbi.gov/about-us/cjis/ucr/leoka/2013/tables/table_44_leos_fk_race_and_sex_of_known_offender_2004-2013.xls
cop_killer_race <- c("White", "Black", "Asian", "Other")
cop_killer_quanity <- c(289, 243, 9, 24)
variable <- rep("Killed Police", length(cop_killer_race))
percent <- cop_killer_quanity/sum(cop_killer_quanity)
cop_killer <- data.frame(race=cop_killer_race, quanity=cop_killer_quanity, type=variable, percent=percent)
 
# People killed by cops
# Source killedbypolice.net (May 2, 2013)
cop_killed_race <- c("White", "Black", "Hispanic", "Other")
cop_killed_quanity <- c(782, 464, 302, 26)
variable <- rep("Killed by Police", length(cop_killed_race))
percent <- cop_killed_quanity/sum(cop_killed_quanity)
killed_by_cop <- data.frame(race=cop_killed_race, quanity=cop_killed_quanity, type=variable, percent=percent)
 
#Population Data
population_race <- c("White", "Black", "Asian", "Hispanic", "Other")
population_quanity <- c(196817552, 37685848, 14465124, 50477594, 28116441+2932248+540013)
variable <- rep("Population ", length(population_race))
percent <- population_quanity/sum(population_quanity)
population <- data.frame(race=population_race, quanity=population_quanity, type=variable, percent=percent)
 
# Bind the three data frames
data <- rbind(population, killed_by_cop, cop_killer )
 
# Calc the placement of the percent text in the graph
df <- data
df <- transform(df, mid_y = ave(df$percent, df$type, FUN = function(val) cumsum(val) - (0.5 * val)))
 
# Plot
ggplot(data=df, aes(x=type, y=quanity, fill=race, label=paste(round(percent*100,1),"%"))) +
geom_bar(stat="identity", position = "fill") + labs(x = "", y = "Percent", fill = "Race") +
geom_text(aes(y = mid_y)) + theme_bw() +
annotate("text", label = "HallwayMathlete.com", x = 2, y = -.03, size = 4, colour = "gray")
 
######### By Gender ###########
# Gender Women killed
# https://www.fbi.gov/about-us/cjis/ucr/leoka/2013/tables/table_44_leos_fk_race_and_sex_of_known_offender_2004-2013.xls
cop_killer_gender <- c( "Female", "Male", "Not Reported")
cop_killer_quanity <- c(13, 551, 1)
variable <- rep("Killed Police", length(cop_killer_gender))
percent <- cop_killer_quanity/sum(cop_killer_quanity)
cop_killer <- data.frame(race=cop_killer_gender, quanity=cop_killer_quanity, type=variable, percent=percent)
 
# People killed by cops
# Source killedbypolice.net (May 2, 2013)
cop_killed_gender <- c("Female", "Male","Not Reported")
cop_killed_quanity <- c( 177,2916, 2)
variable <- rep("Killed by Police", length(cop_killed_gender))
percent <- cop_killed_quanity/sum(cop_killed_quanity)
killed_by_cop <- data.frame(race=cop_killed_gender, quanity=cop_killed_quanity, type=variable, percent=percent)
 
#Population Data
population_gender <- c("Female","Male")
population_quanity <- c(143368343, 138053563)
variable <- rep("Population ", length(population_gender))
percent <- population_quanity/sum(population_quanity)
population <- data.frame(race=population_gender, quanity=population_quanity, type=variable, percent=percent)
 
# Bind the three data frames
data <- rbind(population, killed_by_cop, cop_killer )
 
# Calc the placement of the percent text in the graph
df <- data
df <- transform(df, mid_y = ave(df$percent, df$type, FUN = function(val) cumsum(val) - (0.5 * val)))
 
# Plot
ggplot(data=df, aes(x=type, y=quanity, fill=race, label=paste(round(percent*100,1),"%"))) +
geom_bar(stat="identity", position = "fill") + labs(x = "", y = "Percent", fill = "Race") +
geom_text(aes(y = mid_y)) + theme_bw() +
annotate("text", label = "HallwayMathlete.com", x = 2, y = -.03, size = 4, colour = "gray")
Hallway Mathlete Data Scientist

I am a PhD student in Industrial Engineering at Penn State University. I did my undergrad at Iowa State in Industrial Engineering and Economics. My academic website can be found here.