A federal judge has rebuffed an attempt by Attorney General Maura Healey to avoid being questioned in Texas by attorneys for Exxon Mobil, setting the stage for an extraordinarily rare deposition of a sitting AG.

U.S. District Court Judge Ed Kinkeade for the Northern District of Texas issued a brief order yesterday simply stating he was denying Healey's request "after careful consideration."

He did not elaborate.

In April, Healey launched her probe into whether the $171-billion Texas-based Exxon Mobil Corp. has deceived consumers and investors about the potential environmental hazards of fossil fuel. If Healey prevails, Exxon Mobil would be forced to disclose records dating back to 1976 on what it knew about global warming and climate change.

Kinkeade last month ordered Healey to appear in Dallas Dec. 13 to answer questions about the probe, citing his "concern" about whether she launched her investigation "with bias or prejudgment about what the investigation of Exxon would discover."

Lawyers for Healey had argued unsuccessfully to vacate that decision, contending in a court filing, "Well-established precedent requires that depositions of high-ranking officials only occur in exceptional circumstances that are not present here. … Allowing discovery to go forward here would set a troubling precedent by allowing the target of a state government investigation to confound and effectively halt state law enforcement efforts by filing suit in the target's favored federal forum and permitting the target to ‘investigate the investigator.' "

“Our position in this ligation is that the authorities in Texas, and specifically the federal court down there, has no jurisdiction over state attorneys general and the work of their offices," Healey told the Herald last month. “It's been disappointing to see Exxon fight the request for basic information. Our job as attorneys general is to be able to ask questions."

Kinkeade, noting that Exxon Mobil suspects Healey was attempting “to satisfy a political agenda," issued a written ruling last month saying he needed to know more about what was behind her civil investigation demand before he finds for either side. He noted that Healey, along with New York Attorney General Eric Schneiderman and former Vice President Al Gore, took part in an “AGs United For Clean Power" press conference three weeks earlier, where Healey announced her plan to hold Exxon Mobil accountable.

Tomorrow, Exxon Mobil attorneys are expected to be in Boston for a hearing at Suffolk Superior Court, at which they will try to get Healey's investigation dismissed on First Amendment grounds.

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