The first degree murder is an intentional act of killing someone which is very disapproving and in almost every country of the world it is one of the biggest and most heinous crimes.
On the contrary, there is a little relaxation to the culprit in the second degree murder because this murder happened unintentionally in which the murderer did not want to kill someone. It happens in an unplanned and sudden way.
The direct murder holds severe consequences as compared to second degree murder. In most parts of the world including America, the penalty for the first class murder is life imprisonment and in some cases death penalty can also be given to the murderer.
However, in the second degree murder, the punishment is usually an imprisonment between 20 to 80 years. In many states of U.S.A. people involved in second degree murder are imprisoned for 20 years and in some cases the punishment goes up to 40 years.
The first degree murder leads to target killing no matter whatever is the reason of killing and in this type of murder, there is no relaxation for the killer and the court of justice gives the maximum punishment.
In contrast, the second degree murder a little complicated as there are many things involved that determine of how much punishment should be given to the killer. It depends on the way a murder happens.
In the first degree murder, the intention of the murderer is straight and clear that he wanted to kill someone and that is why; he deserves death penalty or life imprisonment.
In the second degree murder the murderer had no intention of killing a person and he does it accidentally. In such case, the court of justice will evaluate the situation in which the murder took place and then punishes the culprit accordingly which is usually 20 years imprisonment.