Shootings at a Pittsburgh synagogue and at a Kentucky grocery store -- as well as the mailed pipe bombs to Democratic leaders, CNN and some of President Trump's critics -- have all been described as being motivated by hate.
Suspects were arrested in all three incidents over the past week, but only the alleged Pittsburgh shooter is being charged with a hate crime.
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One explanation, several former prosecutors told CNN, is that hate crimes are more difficult to charge and prosecute than other criminal charges, largely because they require law enforcement to prove a specific motivation of bias.
"Generally (for hate crimes), a prosecutor has to prove to a jury beyond a reasonable doubt not only that the defendant committed a murder or a crime ... but also that the defendant committed the crime for a very specific reason," said Elie Honig, a CNN analyst and former prosecutor.
Regular criminal charges, though, have no such demand to prove motive.
"As a prosecutor, you always want to be able to explain motive, but there are times when the law often does not require you to prove motive," he said.
The complexities of the issue were reflected in comments by Mitch McConnell on Monday. The Senate Majority Leader said he believes the recent shootings are hate crimes -- but he also acknowledged that he wasn't sure if that was legally accurate.
"If these aren't definitions of hate crimes, I don't know what a hate crime is," McConnell told reporters Monday. "And I know that's a legal determination that's going to be made by others, but that certainly is my opinion."
McConnell's comments help illustrate the contrast between the general understanding of a hate crime compared to its legal definition -- an important distinction as authorities pursue prosecutions in these high-profile cases.
Why one attack is seen as a hate crime and the other is not
That added hurdle of proving motive partly explains McConnell's hesitancy to legally define both shootings last week as hate crimes.
The suspect in the synagogue shooting, Robert Bowers, targeted a Jewish place of worship, made anti-Semitic statements during and after the shooting and extensively targeted Jews on social media.
For those reasons, he is being charged in federal court with hate crimes, including 11 counts of obstruction of exercise of religious beliefs resulting in death. He could face the death penalty if he is convicted.
However, the white man accused of fatally shooting two black people in a Kroger grocery store in Jeffersontown, Kentucky, has not been charged with hate crimes at this point.
The suspect, Gregory A. Bush, was arraigned on two counts of murder and 10 counts of wanton endangerment and is being held on $5 million bond, according to CNN affiliate WAVE.
Prior to the shooting, Bush allegedly tried to enter a predominantly black church nearby but was unable to get inside, officials said. Investigators are looking into reports that Bush told a bystander before he was captured that "whites don't shoot whites."
The case "appears as if it is" a hate crime and is being investigated as one, Jeffersontown Mayor Bill Dieruf told CNN on Monday. Russell M. Coleman, the US attorney for the Western District of Kentucky, also said federal investigators are looking into potential civil rights violations such as hate crimes.
So why has one man been charged with hate crimes but not the other? CNN law enforcement analyst James Gagliano said that the Pittsburgh shooter's anti-Semitic remarks to police at the scene made connecting the dots fairly easy.
In general, though, officials act in an abundance of caution and investigate more extensively before applying hate crimes charges because of that need to prove motivation.
"It's trying to intuit intent," Gagliano said. "And that's a very difficult thing sometimes."
Still, he said he believed the Kroger shooting investigation would move in that direction in the near future.
"Does there appear to be enough there that you could charge this as a federal hate crime? I think the answer yes," he said. "It just hasn't happened yet. But that doesn't mean it's not going to happen."
Why hate crimes are underreported
There were a total of 6,121 hate-crime incidents reported in the US in 2016, including nine hate crime murders, according to FBI statistics. The Justice Department also released updated statistics on hate crimes, saying in a release that over the past 10 years it has charged more than 300 defendants with hate-crimes offenses, including 50 defendants in fiscal years 2017 and 2018.
But legal experts say the FBI's hate-crime data is grossly undercounted because the reports are provided voluntarily by police departments, and not every department participates.
A national survey by the Bureau of Justice Statistics found there were an estimated 293,800 violent and property hate-crime victimizations in 2012 alone -- about 50 times higher than the FBI's count. An estimated 60% of those hate crime victimizations were not reported to police, the data shows.
That's one reason the Lawyers' Committee for Civil Rights Under Law started the Stop Hate Project, said policy counsel Nadia Aziz. The Stop Hate Project offers training to law enforcement agencies and prosecutors on how to properly investigate and prosecute hate crimes, she said.
"It takes a village in that sense. The hate crime needs to be reported, it has to be investigated appropriately, documented appropriately, so there's enough evidence to prosecute it as that," she said. "You can feel 100 percent in your gut that it's a hate crime but you still have to have the evidence there to prove it."
Aziz also said that there are hateful incidents motivated by prejudice that may or may not be criminal offenses.
"A lot of people experience a lot of hate," she said.
Why hate crime laws matter
Given that hate-crime charges require more legal hurdles and more work, what is the benefit of their use?
The idea is to show the targeted community -- people of that race, religion, disability, ethnicity, gender, sexual orientation or gender identity -- that their lives and identities matter.
"It can send a message as a community and as a society that we're not going to stand for this and we're going to do something about it," said Aziz.
On Monday, the Justice Department announced it has launched a website that will host hate-crimes resources for law enforcement, media, researchers, victims and advocacy groups.
"The tragic attack on the Pittsburgh Tree of Life synagogue just two days ago serves as a stark reminder of the need to protect all of Americans against hate crimes," Deputy Attorney General Rod Rosenstein said Monday at a law enforcement roundtable on improving the identification and reporting of hate crimes.
"In mourning the victims today, we also rededicate ourselves to our commitment to preventing hate crimes. As President Trump said in condemning the crime, there must be no tolerance for anti-Semitism in America," he added.