NEWS broke last week that Rahm Emanuel, now White House chief of staff, lived rent- free for years in the home of Rep. Rosa De Lauro (D-Conn.) – and failed to disclose the gift, as congressional ethics rules mandate. But this is only the tip of Emanuel’s previously undislosed ethics problems.

One issue is the work Emanuel tossed the way of De Lauro’s husband. But the bigger one goes back to Emanuel’s days on the board of now-bankrupt mortgage giant Freddie Mac.

Emanuel is a multimillionaire, but lived for the last five years for free in the tony Capitol Hill townhouse owned by De Lauro and her husband, Democratic pollster Stan Greenberg.

During that time, he also served as chairman of the Democratic Congressional Campaign Committee – which gave Greenberg huge polling contracts. It paid Greenberg’s firm $239,996 in 2006 and $317,775 in 2008. (Emanuel’s own campaign committee has also paid Greenberg more than $50,000 since 2004.)

To be fair, Greenberg had polling contracts with the DCCC before – but each new election cycle brings its own set of consultants. And Emanuel was certainly generous with his roommate.

Emanuel never declared the substantial gift of free rent on any of his financial-disclosure forms. He and De Lauro claim that it was just allowable “hospitality” between colleagues. Hospitality – for five years?

Some experts suggest that it was also taxable income: Over five years, the free rent could easily add up to more than $100,000.

Nor is this all that seems to have been missed in the Obama team’s vetting process. Consider: Emanuel served on the Freddie Mac board of directors during the time that the government-backed lender lied about its earnings, a leading contributor to the current economic meltdown.

The Federal Housing Enterprise Oversight Agency later singled out the Freddie Mac board as contributing to the fraud in 2000 and 2001 for “failing in its duty to follow up on matters brought to its attention.” In other words, board members ignored the red flags waving in their faces.

The SEC later fined Freddie $50 million for its deliberate fraud in 2000, 2001 and 2002.

Meanwhile, Emanuel was paid more than $260,000 for his Freddie “service.” Plus, after he resigned from the board to run for Congress in 2002, the troubled agency’s PAC gave his campaign $25,000 – its largest single gift to a House candidate.

That’s what friends are for, isn’t it?

Now Rahm Emanuel is in the White House helping President Obama dig out of the mess that Freddie Mac helped start.

The president’s chief of staff isn’t subject to Senate confirmation, but his ethics still matter. Is this the change that we can depend on?