Step 1: Note the reaction conditions.
Nitration of aniline uses a strongly acidic mixture of concentrated \(HNO_3\) and \(H_2SO_4\). In this acid medium most of the aniline becomes protonated to the anilinium ion \(C_6H_5NH_3^+\).
Step 2: See how the directing nature changes.
The free \(-NH_2\) group is ortho/para directing and ring activating. But the protonated \(-NH_3^+\) group is positively charged, so it pulls electrons away and behaves as a meta directing, deactivating group.
Step 3: Realise both species are present.
A small amount of free aniline still reacts and sends the nitro group to ortho and para, while the protonated form sends it to meta. So we get a mixture from all three positions.
Step 4: Recall the observed product ratio.
Experimentally direct nitration of aniline gives about 51% ortho, 47% para and only about 2% meta derivatives.
Step 5: Conclude.
The product distribution is 51% ortho, 47% para, 2% meta.
\[ \boxed{51\%\ \text{ortho},\ 47\%\ \text{para},\ 2\%\ \text{meta}} \]