(Bloomberg Politics) — Anyone who watched (or endured) this week’s House Oversight grilling of Jonathan Gruber saw Republicans become obsessed with one particular micro-scandal.

Gruber, quite famously, had been paid around $400,000 by the Obama administration (or, as Republicans put it, by the American Taxpayers Whom He Called Stupid) for his consulting and health care modeling.

Less famously, and as explored fitfully by conservative media, Gruber had been paid more by states. As the #Grubergate headlines grew in size, the state of Vermont got skittish about the work its favorite MIT professor was doing on the coming single-payer health care plan.

Republicans, at the congressional hearing, including the chairman, Rep. Darrell Issa, R-Calif., demanded that Gruber tell them how much money he’d made. Taking a dive, Gruber repeatedly refused to confirm their numbers (“Was it $2.5 million or $2.8 million?” asked Michigan Rep. Kerry Bentivolio) and directed questions to his counsel. After the hearing, NBC News reporter Kelly O’Donnell followed Gruber (on camera) and kept asking about the total payments as the witness stared blankly ahead.

It was a strange line of questioning. “Did Issa really know for a certainty that all the money Gruber may have been paid by a state government was the result of federal funding?” asked Rick Ungar in Forbes. “I really don’t think so. Did Chairman Issa know whether his committee was entitled to work product done by Gruber for a state government that may be protected work product and that Gruber might not be permitted to disclose this information?”

He didn’t — but he wants to find out. On his way out the door, Issa has subpoenaed Gruber and asked for:

1. All documents and communications to or from any federal, state, or local government employee, including, but not limited to, any document or communication referring or relating to the Patient Protection and Affordable Care Act (PPACA) or federal and state health care exchanges.

2. All documents and communications referring or relating to funding, for research or otherwise, from any federal, state, or local government agency, including, but not limited to, any contract(s) with a federal, state, or local government agency.

3. All documents and communications referring or relating to work product produced to any federal, state, or local government agency, for any purpose, including, but not limited to, the results of any and all economic models or simulations.

It’s one final pearl dive, albeit one that incoming Chairman and Utah Rep. Jason Chaffetz will happily strap on the SCUBA gear for. The goal, as before, is to find Gruber gabbing about something that could bolster the legislative arguments for states to undo PPACA, and bolster the legal arguments for the Supreme Court to rule against the government and argue that state exchanges were never meant to have subsidies. (This has become an article of faith among Republicans.)

If Gruber digs through his archives and finds nothing incriminating? Well, he served his purpose already.

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