Each person does have some good in them, and the reason is because God created us in His image or likeness. We aren't like all the other animals; God gave us souls, and because of that we know the difference between right and wrong.
But we also have another side to us—a dark side that has been caused by sin. Yes, we have good within us—but we also have evil. Instead of putting God at the center of our lives, we have put ourselves, and we serve self instead of God. To put it another way, our minds and hearts are a complex mixture of good and evil—and all too often evil dominates. Jesus said, "For out of the heart come evil thoughts, murder, adultery, sexual immorality, theft, false testimony, slander" (Matthew 15:19).
This is why we each need Christ, for only He can forgive us, and only He can come into our lives by His Spirit and begin to change us. We cannot conquer sin on our own; we aren't strong enough. Only God can tame the human heart—and He will, as we yield ourselves to Christ. Have you opened your heart to Him?
What your community has experienced is very sad, and I pray you may find God's peace and comfort. But most of all, I pray that we may each examine our own hearts and lives, and realize that no matter how good or bad we are, we all need Christ.