In the late 1700's the number of free African American people in Virginia grew due to the passage of a law the encouraged what?

In the late 1700s, the number of free African Americans in Virginia grew due to the passage of a law that encouraged the emancipation of enslaved individuals. This law allowed slaveholders to free their slaves more easily, particularly if those individuals had served them faithfully or had been born to free mothers. As a result, some enslaved people gained their freedom, leading to a small but significant increase in the free Black population in the state.