If you have stopped reeling from the IRS targeting scandal, here is the latest shocker: the Treasury Department has now admitted that government officials improperly accessed and scrutinized confidential tax records of several political candidates and campaign donors. Yet, the Justice Department refused to prosecute the cases.

This information came to light when Republican Senator Charles Grassley requested information. An investigation turned up four cases since 2006 in which unidentified government officials snooped through tax records without permission. Three of the cases turned out to be “inadvertent” but one was a “willful” unauthorized access and it was referred to the Justice Department with a recommendation that no prosecution be brought.

Grassley sounded off to the Washington Examiner:

“With the IRS on the hot seat over targeting certain political groups, it’s particularly troubling to learn about ‘willful unauthorized access’ of tax records involving individuals who were candidates for office or political donors. The public needs to know whether the decision not to prosecute these violations was politically motivated and whether the individuals responsible were held accountable in any other way.”

“Although this may not be indicative of widespread targeting, any instance is cause for concern. Even more alarming, in at least one instance TIGTA referred evidence of ‘willful unauthorized access’ to the United States Attorney’s Office, but criminal prosecution was declined. Decisions such as these directly impact the political process and should be subject to the scrutiny of the American public.”

Neither the identities of the government officials who accesses the records nor the identities or political parties of those whose records were accessed have been released.

If you have an unsettling feeling in your stomach over this news it’s probably because you are uncomfortable with the fact that somebody could rifle through your tax returns.

Part of our freedom is the right to expect some privacy. Personal tax records are not and should not be part of the public domain. Unlike public charities whose 990 tax forms are accessible by anyone, Joe Smalltown has a reasonable expectation that agents entrusted with access to such sensitive information will not abuse their privileges.

This latest admission also calls into question the IRS’s denial that any tax records of political candidates or donors were improperly accessed.

Even bigger questions linger in my mind: what happened to the information that was accessed? How did those officials use the information they stumbled across? Was it shared? Did someone tip off a reporter or the many watchdog groups that are always looking to connect donors to unpopular causes for easy targeting by grassroots supporters.

Grassley doesn’t think this is “indicative of widespread targeting,” but months ago when the IRS scandal about the targeting of conservative groups broke, doubters argued it was just limited to a handful of rogue agents. Now we know differently. We’ll see what comes of this new wrinkle.