The man jailed on suspicion of killing three people at two separate Jewish facilities in Kansas City, Missouri, over the weekend already had a long dossier in the Southern Poverty Law Center's database of extremists. Frazier Glenn Miller, also known as Frazier Glenn Cross, spent almost his whole adult life in the Ku Klux Klan and other similar white supremacy groups. He's also had several run-ins with the law, including a three-year stint in a federal prison on weapons charges. 

Source: SPLC

Overland Park Police Chief John Douglass told reporters on Sunday that the shootings were being investigated as a hate crime, a line of questioning that Miller's history overwhelmingly supports. Miller, 73, first joined an anti-Semitic group in the early 1970s: the National States’ Rights Party. But according to the Southern Poverty Law Center's lengthy "intelligence file" on Miller, he later testified that he left the group because it was “made up mostly of elderly people who were not that active.” Soon after, Miller joined the National Socialist White People's Party of America (as in the Nazis), and was active in the group when some of its members shot and killed marchers from the Communist Workers Party in Greensboro, North Carolina, in 1979. If his history is any indication, that sort of action was more suited to Miller's tastes. 

In 1980, Miller founded the Carolina Knights of the Ku Klux Klan, and began stockpiling weapons and training supporters in paramilitary exercises. The SPLC explains his approach to running a KKK group, which was part of a new, more militant sect of leaders in the white supremacist organization: 

Miller represented a new, militant breed of Klan leaders in the 1980s, preferring fatigues over the traditional Klan robe and training his troops in military tactics. He was not averse to publicity and began holding rallies and marches on a near-weekly basis up and down the Atlantic Seaboard. He announced his goal was to create a Carolina Free State, which would be an “all-white nation within the bounds of North and South Carolina.” He said his enemies were “niggers” and Jews. He boasted of having supporters at Fort Bragg, the nearby Army base that was home to a large contingent of U.S. special forces. 

And here's where Miller's anti-semitism became personal for the Southern Poverty Law Center. In 1984, the group, led by then president Morris Dees, sued Miller's KKK wing for a string of episodes of intimidation in and around North Carolina: 

The SPLC lawyers did not know it at the time, but Miller had ties to The Order, a white nationalist terrorist organization whose members assassinated Denver talk show host Alan Berg just 13 days after the SPLC filed suit. The leader of the group, Robert Mathews, had given Miller $200,000 in cash that was part of the  $3.8 million stolen during an armored car robbery. It was later revealed that Dees was at the top of The Order’s hit list. Miller testified in the 1988 trial of other white supremacists that Mathews told him “they were thinking about killing” Dees. 

Less than a year after coming to an agreement with the SPLC, Miller was found violating that order, once again forming a paramilitary white supremacist group. He spent 6 months in jail for violating the order. When he emerged, he sent a note to supporters of The Order urging them to kill “our enemies." He even gave out a point system for his targets: " “Niggers (1), White race traitors (10), Jews (10), Judges (50) Morris Seligman Dees (888).” 

Miller spent three years in jail after the FBI caught up to him, in part because of that threat against Dees, and in part because he was found with a massive stockpile of weapons. As part of his plea deal, Miller testified in a sedition trial against over a dozen members of the KKK. He laid pretty low after that — one would suspect that Miller was not welcome in the movement after testifying against many of his own — with a few exceptions. In 2010, for instance, Miller ran for U.S. Senate in Missouri.  His website documents that campaign with a series of pledges for "when elected:" 

I'll sit down with White, Black, Hispanic, and Asian representatives, and with reasonable minority civil rights leaders, and negotiate with them, free from jewish interference... I'll work with all gentile representatives and all gentile civil rights groups, to expose the jewish domination of the US government, the mass media, the federal reserve bank, and the decadent American culture.

He got seven votes.

During his campaign, Miller also appeared on Howard Stern as something of a racist curiosity, where he mentioned that lately he'd been active on a racist message board called Vanguard News Network. "That’s a sad commentary for our politicians in Washington," Miller told Stern about the rest of Congress, presumably with whom he hoped to work. "They’re all a bunch of whores for Israel. They’re all corrupted to the core. And they are traitors to America.” When Howard Stern asked whether he hated the "jews" or the "blacks" more, Miller responded "Jews," without hesitation. "White people are in bondage to you Jews," Miller told Stern. 

It seems that Miller has devoted his entire life to railing against and threatening black and Jewish people, and there many groups who had kept a watchful eye on him for some time. But having never actually acted on his threats (at least not directly), there is still some shock that he finally crossed that line.

The Southern Poverty Law Center first identified Glenn Miller as the suspect in Sunday's shootings, after a conversation with his wife. Before the shooting, his wife told the organization, he spent his morning at a local casino.