One answer might be found by going back to Romans 12. At the end of Romans 12, Paul is reminding us that judging and justice are not ours. He tells us that we ultimately fall under God's authority but then in the thirteenth chapter he reminds us that we are under the authority of government as well.
I think this all must be tempered with Jesus' obvious call for social justice, though. He always reached out to the lost and least and I think His anger would rise when those folks are not treated fairly. But ultimately, Jesus, too, recognized the need for and authority of government.
Back to Romans 13, in verses 8 - 10, Paul also has a call for justice -- treating others with love. And in verses 11 - 14, he brings us back to the ultimate call that God place son our lives.
So Paul wraps a lot into this text, touching on the authorities we fall under -- government, love for others (justice), and God.