A prominent Minnesota think tank says it will refuse a request by a top U.S. Senate leader to divulge whether it has given money to a conservative nonprofit that has championed "Stand Your Ground" laws around the nation.

"It's nobody's business," said Kim Crockett, chief operating officer for the Center of the American Experiment.

The Senate inquiry came in an Aug. 6 letter signed by Illinois Democrat Dick Durbin, assistant majority leader or "whip," who is holding a hearing next month on the laws, which some have blamed in the Florida shooting of Trayvon Martin.

Durbin says he is "seeking clarification" about the legislative positions of nonprofit groups with tax-exempt status that he believes have given money to the American Legislative Exchange Council (ALEC), a conservative group that has championed "Stand Your Ground" laws now in effect in 26 states.

Liberal groups have derided the laws as "shoot first" because they expand the self-defense rights of purported crime victims.

Crockett and Center of the American Experiment President Mitch Pearlstein have called Durbin's request a "witch hunt" intended to dry up funding for ALEC. In a fundraising pitch Wednesday, the two Minnesota think tank leaders wrote, "Durbin should be ashamed of himself for the naked abuse of power evidenced by his letter."

They also called on Minnesota Democrat Al Franken, who serves on the Senate Judiciary subcommittee that is holding the hearing, to "join us in denouncing Mr. Durbin's thinly veiled threat and abuse of his office."

Crockett said that the center has complied with all laws regulating tax-exempt organizations and that it is not required to publicly identify any other organizations it might help.

The center reported zero in grants and other assistance to governments and organizations in 2010 and 2011. Internal Revenue Service filings are not yet available for 2013, the period for which Durbin seeks disclosure.

Durbin's letter notes that ALEC develops model bills for legislators, including the "Stand Your Ground" bill based on Florida's self-defense law that "provides immunity for certain uses of deadly force."

Durbin noted that the council does not maintain a public list of corporate members and donors. The letter also cites "public documents" indicating the center as a funder.

"I acknowledge your organization's right to actively participate in the debate of important political issues," Durbin wrote. "And I recognize that an organization's involvement in ALEC does not necessarily mean that the organization endorses all positions taken by ALEC."

But Durbin said his subcommittee on the Constitution, Civil Rights and Human Rights wants to know whether the center provided funding to ALEC this year and whether it supports the "Stand Your Ground" legislation that ALEC put forth as a national model. He requested the answers by Sept. 1.

Crockett said Durbin's inquiry represents a federal intrusion into state criminal laws, as well as an inappropriate use of his office to pursue a political agenda.

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