The Internal Revenue Service (IRS) demanded that limited government and tea party groups produce Facebook posts, donor lists, and even what books group members were reading, reports Politico.

The IRS’s hardball political tactics were all part of a strategy to relegate conservative groups to a “state of purgatory” that kept their tax-exempt statuses in limbo to neutralize their effectiveness, says Rep. Darrell Issa (R-CA).

The strategy worked: over 80% of the conservative groups targeted were delayed more than a year, and some cases were left open for over three years, according to the IRS Inspector General’s report released late Tuesday.

The thin 54-page IG report, however, raises more questions than it answers, names no names, and contains gaping holes.

The report, for example, does not examine the possible connections or alliances between the IRS personnel who implemented the conservative targeting strategy and outside political operatives or campaigns. Instead, the IG auditors merely asked IRS personnel whether they were “influenced by any individual or organization outside the IRS” and, not surprisingly, “all of these officials stated that the criteria were not influenced by any individual or organization outside the IRS.”

That was the extent of the IG’s “investigation” into whether the IRS’s targeting of conservative groups involved coordination with campaigns or political operatives.

The IG report ignored core issues at the heart of the scandal. It did not, for example, mention the IRS’s leaking of conservative groups’ tax materials to media organizations. As Breitbart News reported yesterday, the progressive-leaning investigative journalism group ProPublica admitted that the IRS officials at the heart of the scandal gave them “confidential” tax-related documents of conservative groups that were “not supposed to be made public” and that ProPublica received no similar documents for liberal groups–all facts the IG report curiously failed to include.

Also missing from the report by the Treasury Department–overseen by President Barack Obama’s former chief of staff-turned-Treasury Secretary Jack Lew–was any mention of claims that one of Obama’s reelection campaign co-chairmen, Joe Solmonese, may have used leaked IRS documents from a conservative group, the National Organization for Marriage (NOM), to attack his GOP challenger Mitt Romney.

The IG report also failed to mention the IRS’s targeting of Billy Graham, the targeting of pro-Israel groups, the expediting of Obama’s brother’s tax-exempt group, or the IRS’s demands that conservative educational groups release lists of the high school and college students it trained.

Indeed, the IG report was so incomplete that it even admitted inspectors “could not specifically determine who had been involved in creating the criteria” used to go after conservative groups.

Even ardent Obama supporters, like top Democrat on the House Oversight Committee Rep. Elijah Cummings (D-MD) are expressing frustration with the IRS scandal. “I think laws were probably broken,” said Cummings, “but at the least there have been some improper actions on the part of the IRS.”

Cummings added: “I’d love for my committee to have a hearing on this. Because I have great concerns about what they knew, when they knew it, and what if anything they did about it, whether or not they were honest with the Congress.”

Senate Minority Leader Mitch McConnell (R-KY) agrees.

“No more stonewalling, no more incomplete answers, no more misleading responses, no holding back witnesses, no matter how senior their current or former positions–we need full transparency and cooperation,” said McConnell.