For as many as have sinned without law shall also perish without law: and as many as have sinned in the law shall be judged by the law;
All Commentaries on Romans 2:12 Go To Romans 2
Augustine of Hippo
The apostle did not mean to say that those who sin in ignorance will suffer worse punishment than those who know the law. It seems that it is worse to perish than to be judged. Rather the apostle here was merely distinguishing between Jews and Gentiles.