In the spring of 1883, an election was held for the legislature tasked with approving the modifications; it was then that Nacu won his first seat in the Assembly of Deputies.
Together with PNL members V. A. Urechia, Dimitrie Gianni and Alexandru Băicoianu, Nacu formed part of a committee that launched a public appeal to rebuild the gutted property.
In the latter capacity, he oversaw the adoption of a land tax meant to discourage absentee ownership of estates.
On March 13, the opposition met in Bucharest to demand that King Carol I dismiss the government; the armed forces intervened decisively in an unsuccessful attempt to keep the crowd from entering the royal palace.
The outbreak of a peasant uprising in the areas surrounding Bucharest on March 20 impelled Carol to ask for Brătianu's resignation, which put an end to Nacu's tenure.