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Second victim of Phoenix workplace shooting dies

Markow-Kent Photography, Beth Entringer via AP

Mark Hummels was representing Steve Singer in litigation with Arthur Douglas Harmon of Phoenix. Harmon was found dead Thursday of an apparently self-inflicted gunshot wound.

A prominent Arizona lawyer has become the second victim to die in this week's workplace shooting in Phoenix, his law firm said Friday.

Mark Hummels, 43, president of the Phoenix chapter of the Federal Bar Association, died Thursday night, according to the law firm, Osborn Maledon PA.

Hummels had been on life support since he was shot Wednesday following a settlement conference between his client, who was also killed, and the gunman, identified as Arthur Douglas Harmon, 70, of Phoenix.

Hummels was representing Steve Singer, 48, chief executive of Fusion Contact Centers, whom Harmon was suing. Singer died shortly after the shootings Wednesday, and Harmon was found dead of an apparently self-inflicted gunshot wound early Thursday in Mesa, Ariz.

A 32-year-old woman was also shot, but her injuries weren't life-threatening.

Fusion, which operates call centers for businesses, had hired Harmon to do refurbishing work at two of its centers in California. In April, Harmon sued the company for allegedly having failed to pay him in full. The company countersued, demanding that he repay what he had already been paid because the work couldn't be completed.

Documents in the lawsuit include threatening letters from Harmon to Hummels, who wanted to depose Harmon and eventually got a subpoena compelling him to testify under oath, a prospect Harmon said in an email message made him "ill."

"Stop sending your harassing and intimidating e-mails," Harmon said in one email message.

In a letter Dec. 15, Harmon told Hummels: "I will expose you for what you are, depriving me and my family of requested documents to prove my case."

The last communication from Harmon in the case threatened to pursue criminal charges against both Hummels and Singer. Harmon did file a complaint with the Arizona Bar, which dismissed it as being without merit.

Hummels began his career as a reporter for the Santa Fe New Mexican before entering the University of Arizona law school. He graduated first in his class and later was a clerk for 9th Circuit U.S. Appeals Judge Andrew Hurwitz when Hurwitz was an Arizona Supreme Court justice in 2004, NBC station KPNX of Phoenix reported.

Hurwitz called Hummels "the most decent and humble man I have ever met."

In a statement, Hummels' law firm said it was "devastated at this news about our beloved friend" and offered sympathy and support for his wife and two children.

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