Call him collateral damage. That’s the plight of NYPD Deputy Chief Michael Harrington, who was indicted in the fallout from the federal corruption case against former corrections union head Norman Seabrook.

Seabrook’s case ended in a mistrial last week. He is accused of taking a $60,000 kickback in return for steering $20 million of union funds to a hedge fund. The feds based their case on the word of Jona Rechnitz, a wealthy real estate investor who has pleaded guilty to fraud charges but whose testimony jurors appear to have rejected.

According to the indictment, Harrington obtained thousands of dollars in business for a security company “run in part by Harrington’s family and which Harrington unofficially helped manage.” The money was allegedly paid by Jeremy Reichberg, a Brooklyn businessman who was also indicted along with NYPD Deputy Insp. James Grant. The feds alleged that Harrington and Grant received lavish gifts for special favors to Reichberg.

Harrington’s family had no part in running the company, according to police sources, who spoke anonymously to talk candidly on the case. Rather, they said, the company was founded by the radio patrol partner of Harrington’s brother, who was employed there.

From May 2013 to November 2014, Harrington was executive officer to then-Chief of Department Philip Banks.

A longtime friend of Seabrook, Banks appears to have been a target as the probe morphed from Seabrook to the NYPD. Banks introduced Rechnitz to Seabrook after Harrington introduced Rechnitz to Banks. In the end, Banks was not indicted or even questioned. His failing was showing bad judgment in befriending Rechnitz, who police sources say, numerous times called the personal cellphone of Mayor Bill de Blasio from Banks’ office.

The mayor has denied any wrongdoing, and prosecutors did not file charges against de Blasio.

Meanwhile, the feds say they will retry Seabrook. “We look forward to a retrial where we will present again the powerful proof of how Seabrook allegedly sold his duty to safeguard correction officers’ retirement money . . . in exchange for cash bribes,” Acting U.S. Attorney Joon Kim said in a statement.

And Harrington? He was indicted in June 2016 and forced to retire. His trial date is set for April.