A New York state law barring discrimination based on gender expression or gender identity takes effect Feb. 24, 30 days after its approval by Gov. Andrew M. Cuomo.

The Gender Expression Non-Discrimination Act (GENDA) made New York the 20th state to enact protections for transgender people and others who face bias for how they express or identify their gender. It had been bottled up as a one-house bill for 16 years but won quick passage after Democrats...