Is the death penalty neccessary in society?

The implementation of the death penalty has been present ever since the medieval times of the world. It is versatile due to the many functions it serves, as well as the abundant ways it is carried out via, but these revolves around basically the main concept of using death to condemn or get rid of certain 'scum' of the society or country, government or any other authority. The debate on its existence, however, focuses on human rights on life, additionally justice as well.
People usually relate justice to getting rid of evil people. This is due to the fact that by so called killing evil people, we make life safer and better for others. Therefore, since throughout the times the main objective of death penalty is to remove criminals or scum that do people no good, but harm rather, the main benefit of the death penalty would be to prevent the latter to inflict more harm on the people, as well as to clear the atmosphere of fear and insecurity in society. Take for instance a corrupted society, leading to the decline of power of the law. Criminals are free to roam and commit crimes, instilling fear into the hearts of many as they may be victims anytime. Security and safety are hence compromised in such a place, making it a place not suitable for inhabitation. Henceforth, it is essential to get rid of these criminals by meting out punishments so that they learn their lesson so as not to repeat their mistakes such as via jail terms or caning and fines, consequently they repent from the fear of the punishments reenacting in their lives. For hardcore criminals which are seen as hopeless, or their crimes are too unpardonable, they must be removed so as to deter the possibility of repeat of these crimes which will harm the general public.
Punishments not only serve to 'persuade' a criminal to change his ways the hard way, but also to set an example for potential criminals to think twice before commiting the unlawful act. Witnessing or knowing about such punishments inflicted on the criminals deter the potential latter from doing what they should not to break the law. Coincidentally, since humans are mostly fearful of death, the death penalty would attack the core of a potential criminal's heart and mind, and with the rationality to think for their lives outweighing their desire to commit the crime, they are deterred to break the law to harm others. For instance, if people are executed for mere crimes such as in a tyrannical government, it would likely be a crime-free one. Both these points aim to deter hardcore criminals and potential criminals to commit their crimes, mentally and physically.
However, people generally despise or detest criminals for the harm and pain inflicted upon others for their own selfish gains via unethical and immoral methods. Therefore, people's judgement towards their crimes are blinded by their thirst for revenge to inflict the equal punishment on the criminal himself, hence the death penalty may be a consequence from the judgement of the punishment they truly deserve in addition to the hatred for the criminal himself, hence the punishment may be too harsh for the criminal in terms of true justice. Since the death penalty is the harshest punishment in existence, it hence should be abolished to accomodate true justice rather than a mixture of hatred and vengeance itself, by making more punishments more lenient.
In addition, every human has basic human rights, which most essentially is to preserve one's life. By executing a criminal, we are seriously infringing upon the human rights of the criminal. It is felt that we should not play god and impose death penalties on wrong-doers, since every human is counted as equal in society, and that no man is better than the other. By infringing on the most fundamental of all human rights, with the justice system practising such a punishment backed up by the government, which in turn comes up with such regulations to protect human privileges in a human society. How does that differentiate the justice system from criminals? Rather, we should leave god to do the extermination of evil himself. As the saying goes, what goes around comes around, and non-atheists would believe that criminals would get their just deserts.
In conclusion, i feel that the death penalty is indeed essential in the justice system nevertheless. We cannot compromise the safety of others, and that there is no scientific evedence of the presence of any god despite the presence of the various religions and faiths. We must take things into our own hands.