First we can say that God needs no vindication. It is absurd that the creature should put the creator on trial. The challenge is rather to properly understand the issues, and explaining them in 150 words is not possible. We can say the following, though:
The question is phrased improperly. There are no “good” people, “there is none righteous, not even one” (Romans 3:10). That rephrases the question to “why do bad things happen to any people?”
Bad things happen because of sin, which, as it has always done, fouls up the creation and invites the judgment of God.
The more perplexing question is why do good things happen to bad people? That too, is attributable to God, in this case to his amazing grace.