Manhattan District Attorney Cyrus Vance Jr. View Full Caption DNAinfo/Ben Fractenberg

MANHATTAN — The state's top prosecutor should investigate Manhattan District Attorney Cyrus Vance Jr.'s decision not to prosecute Ivanka Trump and Donald Trump, Jr. over evidence they tried to sell condos by using inflated sales figures, one state lawmaker says.

Vance's office had been building a criminal case against President Donald Trump’s two oldest children starting in 2010 based on evidence they misled prospective condo buyers at Trump SoHo into thinking the pricey units were selling better than they actually were, according to a joint report by ProPublica, WNYC and the New Yorker.

But after Donald Trump’s attorney Marc Kasowitz donated thousands of dollars to Vance’s campaign in 2012, the district attorney “overruled his own prosecutors” and had them drop the case, the report states.

In a letter, Assemblyman Dan Quart — whose district includes the Upper East Side and Midtown East — asked state Attorney General Eric Schneiderman to look into Vance’s decision.

“A district attorney must not only adhere to the laws that govern public officials, but be held to a higher standard,” Quart wrote. “[The] revelations, if proven accurate, make clear that Manhattan DA Cy Vance has at the very least, failed to live up to that higher standard.

“Public corruption is a stain on any elected official but it is particularly disturbing when the official himself is entrusted by the public to prosecute wrongdoing,” the letter added.

In response to the report, Vance returned the contributions to Kasowitz, the Daily News reported.

Vance's communications director Joan Vollero on Friday maintained that DA's investigation, which lasted for two years and wrapped up in August 2012, "never produced sufficient evidence to support a criminal prosecution."

The DA's office accepted a contribution from Kasowitz in January 2012 after it underwent a review process aimed at identifying "potential conflicts," but it was flagged and returned "months later" after Kasowitz told the office he was involved in the Trump SoHo matter, Vollero wrote in an email.

Kasowitz made another contribution after August 2012 that was reviewed and "found to be without conflict" in January 2013, she said.

"This vetting process goes far beyond what is required by law, and no attorney, at any time, influenced any decision in the Trump SoHo matter," she wrote, adding that the luxury apartment buyers "reversed course [during the DA's investigation] and took the position that the sellers had not committed any crime against them."

Nevertheless, Quart said it was “incumbent upon the Attorney General to investigate District Attorney Vance for his role in choosing not to prosecute Ivanka Trump and Donald Trump, Jr.”

“The people of Manhattan have a right to know whether their District Attorney is being unduly influenced by campaign donations,” he wrote.

A spokeswoman for Schneiderman’s office declined to comment on Quart’s letter.