Ahead of the 2022 school year, the education technology company 21stCentEd was seeking to expand its presence in New York City’s public schools. So they turned to a man, Terence Banks, whose new consulting firm promised to connect clients with top government stakeholders.

Banks wasn’t a registered lobbyist. His day job, at the time, was as a supervisor in the city’s subway system. But he had at least one platinum connection: His older brother, David Banks, is New York City’s schools chancellor, overseeing the nation’s largest school system.

Within a month of the hire, 21stCentEd had secured a private meeting with the schools chancellor. In the two years since that October 2022 meeting, more than $1.4 million in Education Department funds have flowed to the company, nearly tripling its previous total, records show.

The siblings — along with a third brother, Philip Banks, who serves as New York City’s deputy mayor of public safety — are now enmeshed in a sprawling federal probe that has touched several high-ranking members of Mayor Eric Adams’ administration.