Sen. Rob Portman and Rep. Steve Chabot spoke to a hundreds-strong gathering of tea party activists in near Cincinnati, which has been a focus, or "ground zero," as one tea party leader called it, of the IRS probe following disclosures that agency employees there subjected conservative groups for additional, often burdensome scrutiny when they applied for tax-exempt status.
"The question is, `How high up did it go?"' Chabot said, adding: "And what's going to be done about it?"
The Obama administration has said no senior officials were involved in targeting.
Chabot said investigations are still unfolding, and it's important to follow the facts and not to overreach in drawing conclusions. Portman linked the IRS scandal to the Benghazi attack investigation, and both he and Chabot said the Obama administration must be more forthcoming.
Portman said he finds it hard to believe that a couple of "rogue agents" in Cincinnati were responsible for the conservative targeting and that it was done as an efficiency measure to handle a large number of applications, as was initially suggested. IRS employees in Cincinnati have declined requests for comment, but some former workers in the office have said it was nonpolitical and that they doubt there were any partisan motivations.
Portman said he hoped whistle-blowers would come forward to let people know what happened.
He reiterated that a special prosecutor could be needed to investigate the IRS case, although he's not calling for it yet. He said the possibility of a criminal investigation should at least be used as leverage to push for answers from the Obama administration.
Otherwise, Portman said, "We're going to have to go up to the next level."
GOP U.S. Rep. Brad Wenstrup, a doctor, said the IRS targeting raises troubling questions about how the Obama health care law changes will be carried out, saying people's access might be affected by their political or religious beliefs.
Tea party speakers recounted their experiences with the IRS in a meeting carried live on a website. Cincinnati leader George Brunemann said he and his wife were audited after she became a tea party group treasurer.
Former Ohio Liberty Coalition leader Tom Zawistowski of Kent said the IRS should be abolished, and he urged activists to tell their friends and neighbors that the IRS probe is important to all of them.
"We're all tea partiers now, aren't we?" Zawistowski said.
Russell Hudson, 69, a retired steelworker who came to the meeting from Trenton, about an hour's drive away, said he was concerned about the IRS' conduct.
"It's crazy. It defies imagination," he said.
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