My choice for the 2013 D.C. Person of the Year is U.S. Attorney Ronald C. Machen Jr. Does that mean Machen is the best person of the year, an outstanding example of success to be emulated by all? No.

The D.C. Person of the Year, like the honor bestowed by Time magazine, is given to the individual whose work, for good or ill, has had the most far-reaching impact.

Machen is the most consequential public figure in the District. His nearly three-year-old corruption probe has reached deeply into our system of governance. He has taken down officials who were chosen by the voters. He has induced public leaders to leave office. Consequential.

Machen’s probes have made the city notorious in the eyes of the nation. Consequential.

And his work has exposed our city’s glaring deficiency in public persons with unquestioned integrity. Consequential.

In 2014, as in this year, Machen again will figure prominently in the news as the city heads into another sea of political uncertainty. Democratic primary voters are heading toward an April 1 election not knowing which, if any, of the candidates will be the focus of a federal prosecution. Consider this dilemma:

Mayor Vincent Gray (D) still figures prominently in Machen’s investigation of the illegal payments in the 2010 Democratic primary;

Council member Vincent Orange (D-At Large) has met with federal prosecutors and turned over subpoenaed campaign records;

●Council member Jack Evans (D-Ward 2) has received a grand jury subpoena for records related to contributions by Jeffrey Thompson, the former big-money city contractor and the alleged financier of a shadow campaign (“a well-financed conspiracy,” Machen called it) on behalf of Gray’s 2010 mayoral candidacy;

Council member Muriel Bowser (D-Ward 4) has refused to say whether her campaign has received a subpoena.

Are any of those mayoral candidates now in the clear?

This week I asked Machen’s office if Gray was under investigation, whether the investigation of Orange was now closed, if Evans has been cleared and whether Bowser or her campaign is the subject of a grand jury subpoena.

On Thursday, I received this response from U.S. Attorney’s Office spokesman William Miller: “The investigation into the 2010 mayoral election is continuing and the U.S. Attorney’s Office has no further comment at this time.”

Where does that leave primary voters? Do they choose a candidate who might fall prey to Machen? Should they worry that the prosecutor’s actions may negate their vote?

Uncertainty is not limited to the ballot.

Next spring, around the time of the Democratic primary, at least five individuals who have pleaded guilty to charges — Jeanne Clarke Harris, Lee Calhoun, Stanley Straughter, Vernon Hawkins and former D.C. Council member Michael A. Brown — will be paraded before a U.S. district judge downtown to learn their fates.

Four of them share an involvement with Thompson. Although Brown allegedly received unreported campaign money from Thompson, he made it to the docket on his own: He was caught taking bribes.

All five are said to be cooperating with the prosecution.

If true, in the coming year the local public arena will most likely continue to be roiled by official investigations.

The pursuit of justice may demand such federal intervention. But it comes at a cost. It will be Machen and his prosecutors, and not the voters, who may most influence the local political process.

A stipulation: Machen’s job is investigating crimes. It’s not the U.S. attorney’s fault that some District officials are inclined to break the law. Neither is it his responsibility to ensure that only people with good character and integrity obtain public office. That’s the voters’ job — and some of the results, sadly, speak for themselves.

Machen’s prosecutorial discretion is broad. But he has no warrant to conduct a fishing expedition in wanton pursuit of vague guesses.

Machen and D.C. Attorney General Irvin B. Nathan are now in a dispute over the release of e-mails and other documents related to the city’s decision to enter into a $7.5 million settlement with Thompson’s company. Machen is likely to end up with most of what he wants.

When Machen’s investigation is concluded, however — and if the disputed documents have not been used as evidence — his quest for internal city communications may be evidence of prosecutorial recklessness.

A comprehensive probe of corruption is needed. But a wild inquisition is beneath a Person of the Year, in 2013 or any year.

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