Do you agree with the lawyer's argument that Mobley was born to kill?

My Opinion: Tony Mobley was put in Death row due to a murder he committed. He had a good pretty good life, no past traumas. Butviolent crimes did run in his family, murder, rape, robbery, suicide.And this is all due to the result of a chemical imbalance, it's been passed on from generation to generation. People argue that now due to this chemical imbalance that crime would have no consequence. Since their actions were done accordingly to their "chemical imbalance". if they know it runs in the family they should do something about it, stop that urge of the violent thoughts and doings they want to do.

How can I support my opinion by referring to nature vs. nurture ?