library(Hmisc)

means <- c(2.96, 3.59)

bp = barplot(means, ylim=c(0,6), names.arg = c("Black", "White"), ylab="Support for life in prison without parole", xlab="Race of the convicted teen", xpd=T, width=c(0.2,0.2), xlim=c(0,1), space=c(1,1), main="Black Non-Hispanic Respondents")

se <- c(0.2346, 0.2022)
lower = c(2.48, 3.19)
upper = c(3.42, 4.00)
errbar(bp, means, upper, lower, add=T)

box(bty="O")