As expected, Che Brown, the brother of former D.C. Council chairman and convicted felon Kwame Brown, pleaded guilty this week to a federal charge of bank fraud. Kwame Brown pleaded guilty to a similar charge in June and is serving a six-month sentence of home detention.

Are a judicial tongue-lashing and a curfew in Che Brown’s future, too? We won’t know until March 5, when he is scheduled for sentencing.

More intriguing is what U.S. Attorney Ronald C. Machen Jr. had to say this week about the broader investigation that his office conducted into Kwame Brown’s 2008 reelection campaign. Last week, I suggested that Machen’s probe had come to naught.

While not denying that the federal criminal investigation had fizzled out, Machen sought this week to broaden the impact of the Browns’ encounter with the feds.

Machen contended in a letter released Thursday that Kwame Brown’s guilty plea in D.C. Superior Court to aiding and abetting unlawful cash expenditures for his campaign is a byproduct of the federal investigation. As part of Brown’s plea agreement, Machen wrote, the former legislator “was required to resign from his position as Chair of the D.C. Council.” Machen boasted that “This conviction marks the first time this 35-year-old campaign finance law has ever been criminally enforced.”

The most significant outcome in this case, however, is Machen’s decision to throw the ball back to the D.C. Board of Elections. In July 2011, the board had referred complaints from the D.C. Office of Campaign Finance against Brown’s 2008 campaign to the U.S. attorney for criminal investigation.

Now, Machen is putting the onus back on the Board of Elections and the Office of Campaign Finance to delve into the details and findings in the administrative complaint filed against Kwame Brown.

Although more federal criminal charges in this case are unlikely, Machen suggested there is rich mining in the administrative complaint. He urged the elections board to “vigorously enforce” D.C. campaign finance laws regarding cash contributions and expenditures and failures to disclose financial matters.

The Board of Elections said when it referred the complaints to the U.S. attorney that it retained jurisdiction to pursue the administrative complaint against the campaign filed by the Office of Campaign Finance. The board also said it retained the right to assess “appropriate civil penalties” at a later date.

The shift back to the elections board and campaign finance office should capture the attention of more folks than Kwame and Che Brown.

The District’s 2010 mayoral campaign was marred by the free flow of unreported campaign cash, the unrestrained use of straw donors and undisclosed campaign spending. Those violations land squarely in the bailiwick of the city’s elections board and campaign finance office. Do we ignore the whole scandal and let the violators get away?

Are the Board of Elections and the Office of Campaign Finance up to the job? If they take their cues from the D.C. Council, don’t expect much in the way of enforcement. The District is cursed with legislators who firmly believe campaign finance reform is the devil’s work.

Just last week, the council was given the opportunity to pass a comprehensive package of campaign reforms proposed by Mayor Vincent C. Gray (D). But council members beat a retreat the likes of which has not been seen since Napoleon and his Grande Armée fled Moscow.

Close campaign contribution loopholes? Eliminate “pay to play”? No, no, a thousand times no; if you ask us again, we shall die, seemed to be the council’s response to a request for action on the proposed reforms.

Campaign contributions are the mother’s milk of D.C. politics. And our pols lap it up anywhere they can land their lips.

So it fell to the council’s newly installed chairman, Phil Mendelson, to announce last week that campaign finance reform is “not on the committee markup.” In fact, Mendelson was echoing the sentiments of Muriel Bowser (D-Ward 4), who chairs the committee that oversees campaign finance laws. Bowser recently told The Post’s Tim Craig that her colleagues wanted to go slow. “They’d rather have more time to consider it. They are complicated issues,” she said. Girded with that insight into the legislature’s thinking, how fearless will our campaign and elections officials be?

Here’s hoping the election board’s chairwoman, Deborah K. Nichols, will show the fortitude so lacking in some of our legislative leaders and demand that campaign finance officials vigorously enforce the laws on the books.

Or am I fooling myself? As one city pol might whisper to a cash-bearing lobbyist, “What’s the law between friends?”