Why prisoner get death sentence aftre 4 am and before sun rise?

There are many contradictive statements regarding this topic. The most appropriate answer according to me is that a new day start after 12pm and the people are sleeping till 4 pm so it is a good time to hang the criminals within a few hours of the new day and to make sure he will not see the dawn of the next day. Also the sheriff and his assistants are the only persons allowed to see the execution so it is the right period of time to complete the punishment.