The FBI this week reported a 17 percent year-over-year increase in federal hate crimes across the U.S., the third consecutive yearly rise and the largest jump in federally reported hate crimes since the September 11 attacks. The annual report showed there were 7,175 bias crimes in 2017 involving 8,828 victims. Victims targeted due to their sexual orientation or gender identity comprised 1,470 — or nearly 17 percent — of all victims.

The 1,470 victims were involved in 1,249 separate bias incidents. Nearly 60 percent of these incidents targeted gay men, 25 percent targeted a mix of LGBTQ people, 12 percent targeted lesbians, 3 percent targeted heterosexuals, 2 percent targeted bisexuals and 1 percent targeted transgender and gender-nonconforming people.

The number of hate crimes motivated by anti-LGBTQ bias has remained relatively steady, from a high of 1,256 in 2010 to a low of 1,097 in 2014. Since 2014, the total number has increased every year. But what has also remained constant is the portion of overall hate crimes that are motivated by anti-LGBTQ bias: between 17 and 21 percent. (Note: data on trans and gender nonconforming-related bias incidents starts in 2013.)

The lesbian, gay, bisexual and transgender community is estimated by Gallup to comprise 4.5 percent of the U.S. population, yet according to the FBI’s newly released report, they make up more than 16 percent of federally reported hate crime victims (subtracting those targeted due to their heterosexuality from the 17 percent figure above). The Jewish and black communities also shoulder a disproportionate percentage of federally reported hate crimes: Jewish people comprise an estimated 2 percent of the U.S. population but make up 11.5 percent of hate crime victims, and the black community is an estimated 13.4 percent of the U.S. population but makes up 28 percent of hate crime victims.

Frank Pezzella, a criminology professor at New York’s John Jay College of Criminal Justice, said the increase in this year’s number of federally reported hate crimes is alarming — but still likely a gross undercount of the total number of bias incidents, because many — perhaps most — hate crimes go unreported.

“There is a huge difference between the annual [FBI] hate crime report and the 252,000 hate crime victimizations that are reported each year,” Pezzella explained, referring to the National Crime Victimization Survey (NCVS).

The annual FBI hate crimes report is based on “Uniform Crime Reports,” which are statistics reported to the FBI by state and local law enforcement agencies. However, Pezzella said only 75 percent of the approximately 18,5000 police agencies participate in hate crime reporting, and of those who do participate, nearly 90 percent “report zero hate crimes every year.”

For a better overview of the scale of bias crimes, Pezzella pointed the NCVS, which is administered by the U.S. Census Bureau and asks victims directly about their exposure to crime. Pezzella said the NCVS is a better gauge of bias victimization, in part, because it allows victims who are part of marginalized groups — like undocumented hispanics, blacks and LGBTQ people — to bypass law enforcement.

“The LGBT community,” Pezella explained, “do not report hate crimes, and we argue because of the strained relationship with the police,” he said. He also added that the most common answers to the NCVS question about why respondents don’t report crime are “police apathetic, police bias” and police ineffective.”

Despite what Pezzella perceives as flaws in the FBI’s hate crimes data, which has been published in some form since 1990, he said it still provides useful information.

“There are obvious holes in the data,” he lamented. However, he added, “it does provide us 30 years of baseline figures.”

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