God wouldn't have allowed any inoccent deaths. Again he didn't create the law to kill inoccents, it was to determine what the punishment was for a girl being, "promiscuous in her father's house."
Even if not a single innocent person was killed, is it really a good law? Is death an appropriate punishment for promiscuity or homosexuality? The people that the law was given to rejected capital punishment quite early. Were they bad for not following the punishments given by God or were they good for using human morals to see that killing people is wrong? The laws and how they've been applied clearly reflect the historical context, rather than a continuous unchanging tradition.
To me, the Bible is a human perception of God, if God exists. That's why the laws change. If one of God's characteristics is never changing, then humanity must have changed. Even Jesus, who was supposedly God himself, knew that killing was wrong. He knew that the earlier punishments given by God were wrong. So why would God have given out punishments that God himself knew were wrong?
If God is unimaginably great, beyond human comprehension, how could He ever fit in a single book? If God exists, I believe that He transcends the scripture about Him.