Romans 2:12

All who sin apart from the law will also perish apart from the law, and all who sin under the law will be judged by the law.

(v12, NIV)

Paul has just stated that God shows no partiality. This is with regards to the way in which God will judge. He was talking about God judging according to work and deeds. People in doing good seek for glory, honor and immortality will receive eternal life. However, self-seeking people who reject the truth and follow evil receives wrath and anger. Here in verse 12 Paul begins to address an objection people may raise. People might say that it's unfair because God only gave the Jews the law but he didn't give it to everybody else. If he only gave the law to the Jews then how is God impartial?

As Paul begins to address this objection, he seems to be saying that people will be judged according to what has been given to them and what they do with it. Those who sin under the law will be judged by the law. From reading further in Romans we know that all have sinned and fall short of the glory of God. These people sinning under the law are judged by it and that's not good for them. However, these people who sin apart from the law will perish apart from the law. When talking about these, Paul distinctly says that they will perish. It's not an excuse to say that you didn't have the law and so you didn't know any better. It doesn't matter because you will perish apart from the law when you sin apart from the law. We see later that the law is written on their hearts. However, even so, people even break the laws and truths they have been given in a sense. In their conscious they may recognize that something is "bad" but even those things they cannot keep perfectly. So, not having the law is not a valid argument. Even if you don't have the law, you will perish apart from the law when you sin apart from the law.