The Internal Revenue Service has had a terrible month. That month, which has been low-lighted by its apology for targeting tea party groups for increased scrutiny of their tax-exempt status, has sent the agency's approval ratings into free fall.

A Fox News poll released last week found 57 percent of registered voters profess "not much" or no confidence at all in the IRS. That marked a complete reversal from the last time Fox asked the question in May 2003, when 62 percent had "a great deal" or "some confidence" in the agency. And a Gallup poll released after Fox's finding  showed 42 percent of respondents saying the IRS is doing a "poor" job, double the number who said this in 2009 (20 percent).

Beyond the general ratings, Gallup found 60 percent of Americans think the IRS "frequently abuses its powers" and 62 percent say it's "been given more power than it needs to do its job."

The long-term impact of the news about the IRS' targeting of conservative groups is difficult to pin down, since each poll compares to surveys conducted several years ago. But an April Washington Post-ABC News poll conducted before the news broke offers a useful comparison point: 49 percent held favorable views of the IRS, while 48 percent were unfavorable.

The worsening assessment is most stark among Republicans and independents. Both groups held net positive ratings of the IRS in 2009 -- more rated the group as "excellent or good" than "poor" -- but its image is clearly negative. The drop off has been smaller among Democrats, with the IRS still earning more positive than negative marks.

The current controversy is not the first time the IRS' public image has taken a hit after allegations of abuse.The current backlash follows a similar pattern to a controversy over out-of-control audits of individual taxpayers in the mid 1990s. Six in 10 Americans held "unfavorable" ratings of the agency in a 1997 Pew Research Center poll after a Senate hearing where the IRS was accused of using harsh tactics while conducting audits.

The 1997 affair offers a bit of a silver lining for the IRS. After the agency faded from the headlines, a 2002 Fox News poll found voters with far more positive view: 45 percent of registered voters rated it favorably, 34 percent unfavorably.

Scott Clement is a pollster with Capital Insight, the independent polling group of Washington Post Media.