Here his record is less commendable: his use of science to back racism and elitism was not unusual for the period, but his exclusive focus on the interests of the National Museum led him to questionable practices, such as not returning a collection borrowed from the Museu Paraense for an exhibition.
Netto initially accepted the inscription as genuine, but when his mentor Ernest Renan declared it to be a hoax, he backed down and blamed foreigners for its fabrication.
He hired several foreign scientists as traveling naturalists, including Fritz Müller, Emílio Goeldi, Domingos Soares Ferreira Penna, Hermann von Ihering, Wilhelm Schwacke, Orville Adalbert Derby, and others.
In 1882, the National Museum, directed by him, promoted the Brazilian Anthropological Exhibition, which had international influence.
With the advent of the Republic in 1889 and the exile of Pedro II, Ladislau Netto lost his chief patron and some of his influence.