BerlinRosen also represents the Coalition for the Homeless, a group that refuses to hold Mayor de Blasio accountable for the runaway spike in homelessness during his mayoral administration, and the external nonprofit lobbying arm of City Hall, the Campaign for One New York.

The Campaign for One New York raises big money donations from special interests, who have business before New York City government. How many favors are being traded either by BerlinRosen on its own behalf or on behalf of the de Blasio administration in order to raise large sums of unregulated money for the controversial lobbying arm of City Hall ?

Ms. Rauh's report noted that because BerlinRosen is an unregistered lobbying firm, the public has no transparency into which private corporate clients the firm may represent or how much the firm is being paid -- transparency that does exist for registered lobbying firms, according to Ms. Rauh.

Another issue raised in Ms. Rauh's report is the fact that BerlinRosen can skirt campaign finance regulations that place a cap on campaign contributions for municipal officials.

Not mentioned in Ms. Rauh's report, however, is the fact that BerlinRoses uses the Campaign for One New York to coördinate its political and lobbying activities with City Hall when, during the normal course of an election cycle, such coördination would be deemed a violation of campaign finance law as amended by the Supreme Court's decision in the Citizens United case.

BerlinRosen's lucrative business opportunities are given to it by its access to inside information about the de Blasio administration, and the public has no insight about how BerlinRosen may be exploiting that insider access, except that, on a few occasions, it becomes known that the firm is representing many sides on the same transaction, a revelation that became clear when it was reported that BerlinRosen was being paid by Two Trees Management, a real estate developer on whose behalf BerlinRosen consulted, in connection with a zone-busting real estate development project at the site of the old Domino Sugar factory in Brooklyn. BerlinRosen was representing Two Trees Management at the same time when BerlinRosen was advising City Hall on other matters.

"It was an early example of the position Rosen and his firm occupy in de Blasio's New York : at the nexus between City Hall and private interests," Ms. Rauh said in her investigative report.

As Progress Queens reported in a follow-up article about the New York City Housing Authority, information obtained by Progress Queens revealed that federal authorities had to review whether Mayor de Blasio had any role in a questionable tax break extended to another major real estate developer, Extell Development Company, laying bear concerns that the de Blasio administration may be engaged in unethical conduct.

BerlinRosen also represents Forest City Ratner and SL Green, two other major real estate developers, according to Ms. Rauh's report.

Predictably, two municipal legislators, Councilmembers Corey Johnson (D-Chelsea) and Brad Lander (D-Park Slope), along with another lobbyist, who doubles as a campaign consultant, Hank Sheinkopf, defended the system that begets powerful firms like BerlinRosen.

"There's no laws being broken. They're doing what everyone else has always done," Mr. Sheinkopf said, in part, during Ms. Rauh's report.