(CNN) -- It was a mismatch from the start: a 16-year-old boy, 5-feet, 3-inches tall and 150 pounds, against two reputed Ku Klux Klansmen, the biggest standing 6-feet, 5-inches and tipping the scales at 300 pounds.

Jarred Hensley is shown in Klan garb in a photo posted on the Southern Poverty Law Center's Web site.

Jordan Gruver, an American citizen of Panamanian descent, took a beating that July day in 2006 at the Meade County fair in Brandenberg, Kentucky. He was called names, spat upon, doused with alcohol, knocked to the ground and punched and kicked.

When the blows stopped, Gruver had a broken jaw and left forearm, two cracked ribs and cuts and bruises.

Now, with the weight of the Southern Poverty Law Center behind him, Gruver is fighting back in a civil courtroom. Gruver and the center are suing the Imperial Klans of America, and they hope to win damages large enough to put the supremacist group out of business.

An all-white jury -- seven men and seven women -- was chosen Wednesday to hear Gruver's lawsuit against the Klan and two of its members. They are identified in court papers as "Imperial Wizard" Ron Edwards, and Jarred R. Hensley, the Ohio Klan's "Grand Titan."

Two others -- Joshua Cowles, the Klan's "Exalted Cyclops," and Andrew W. Watkins, the Klan's "Imperial Gothi" and webmaster -- have settled out of court, according to a pretrial brief.

The lawsuit identifies Cowles, Hensley and Watkins as the men who confronted Gruver and insulted him with ethnic epithets while on a recruiting mission at the fair. Hensley and Watkins, the suit alleges, knocked Gruver to the ground and repeatedly struck and kicked him.

The two men already have gone through the criminal courts, striking plea bargains and serving time in the Kentucky state prison system, according to court documents. The others were named as defendants because the Montgomery, Alabama-based center identified them as Klan officers at the time.

Opening statements began under tight security. The center's co-founder, Morris Dees, alleged that Edwards "sent his agents out on a mission," adding, "It was while that mission that Jordan was hurt."

Don't Miss PDF: Read the lawsuit

Edwards, who is representing himself, told the jury he would prove he had nothing to do with the attack.

"I'll prove that I teach them not to go out and commit violence," he said in his opening statement. "I'll prove I did not know they were there."

He added, "I stay within the law. I don't break the law."

At an earlier court deposition, Edwards demonstrated his contempt for the center and its lawsuit by tattooing a profane reference to it on his freshly shaved head.

Hensley, who lives in Cincinnati, Ohio, told CNN affiliate WAVE on Wednesday that he already has paid a price for something he didn't do. He said the legal system was "corrupt," but that he was at the trial "because the law told me." He also is representing himself. Watch what Hensley has to say »

The lawsuit alleges that Edwards, the supremacist group's founder, uses money from Klan dues, contributions and merchandise sales "as his own personal funds."

He lives in a trailer on the Klan's heavily guarded, gated compound in rural Dawson Springs, Kentucky. The compound is the site of the Klan's annual white power rally and music festival, know as "Nordic Fest," according to the suit.

It was at the compound, the suit alleges, that the Klan incited its members to use violence against minorities.

The center is seeking to win a judgment that would allow it to seize up to $6 million in assets.

"We want to win justice for Jordan to compensate him for his injuries and put this group out of business," said center spokesman Booth Gunter. "We've won a number of these suits in the past."

In 2000, for example, the center won a $6.3 million jury verdict that forced Aryan Nations leader Richard Butler to give up the group's Idaho compound. In 1987, a $7 million verdict in Mobile, Alabama, targeted the United Klans of America.

Richard Cohen, the law center's president, said, "The Imperial Klans of America is one of the largest Klan organizations in the country. It promotes violence and intimidation against racial and ethnic minorities, homosexuals and so-called 'race traitors.' While on a recruiting mission, members of this organization targeted and viciously beat our client solely because he has brown skin.

"Our lawsuit seeks justice and compensation for the victim of this brutal hate crime. We also hope that the monetary damages will be sufficient to put the organization out of business and send a strong message to other hate groups and their followers that this type of racial violence will not be tolerated."

The center says the Imperial Klans of America is the second largest KKK group after the Brotherhood of Klans, based in Marion, Ohio.

Estimates of its total membership vary widely, but the center says it has about 23 chapters in 17 states.

Gunter said Edwards' son, Steve, runs another group called the Supreme White Alliance, which has ties to two supremacists accused in a plot to don white tuxedos and assassinate Barack Obama.

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