N.Y.C. Charter § 47: Section 47. Legislative professional staff.

Within appropriations for such purpose, the council shall establish a structure within the City Council and retain professional staff to review and analyze proposed budgets and departmental estimates, requests for new taxes or changes in taxes, budget modifications, capital borrowings and mayoral management reports. Such staff shall assist the committees of the council and Council Members in their analysis of proposed legislation and in review of the performance and management of city agencies.