[things within these parentheses are misspellings and grammar errors that are corrected] 

There [have always been] fierce debates about the existence of [the] death penalty when scar[y] murders and manslaughters [the word "manslaughters" isn't neccesary because you already used "murders"] happen in our society. It's often argued that [the] death penalty can stop serious crimes while others disagree [with] that statement and consider [that the] death penalty make[s] criminals more violent. This essay will discuss both points of view and make [the verb "to present" instead of "to make" would fit better. Example: This essay will discuss both points of view and present a conclusion] the conclusion. <o:p></o:p>

<o:p>[Your first paragraph introduces the topic and give a list of what you will talk about. 1: The death penalty works and 2: The death penalty does not work. It's a good start. The reader knows what will come next in the essay. It is assumed that you will write about point 1 and point 2 in that order. However, the next paragraph you have starts with point 2 so when the reader moves from the first paragraph to the second, they're a little confused because it was assumed that point 1 would be made first. In order to fix that, either switch point 1 and 2 in your first paragraph OR switch paragraph 2 and paragraph 3 to make the essay have a logical sequence of events. </o:p>

[If you wanted to switch paragraph 2 with paragraph 3, you would then use ..."However, many disagree.."

Many disagree and think that [the] death penalty make criminals more violent and aggressive when they've committed serious crimes because there is no heavier punishment than [the] death penalty. Therefore, the criminals will fight against [the police] and sometimes involve innocent citizens during the fight. This essay agree[s] that [the] death penalty is outdated nowadays, and many countries abandon the death penalty because there [is not a] positive relationship between [the] death penalty and crime rates. <o:p></o:p>

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<o:p>[If you wanted to switch paragraph 3 with paragraph 2, you could start with ... "Most people.."] </o:p>

However, most people believe that [the] death penalty can prevent criminals from committing serious crimes because the price of murders is their lives. As a result, kidnappers and [rapists] will let [their] victims go instead of killing them. The punishment for murders is heavier than [that of rapists or thieves]. Besides, some of people who intend to commit crimes will give up because of the heavy punishment. But, this essay disagree[s] [on] that point[x] of view. More research[xx] show[s][that] some criminals don’t care about the law when they commit serious crimes.<o:p></o:p>

<o:p> </o:p>

While most countries [have] remove[ed] [the] death penalty [in the law] or imprison murder[er]s for their lifetime instead, some still think murder[ers] should pay [with] their lives for what they have done [before]. However, there are many ways to prevent crimes through the education and society instead of punishment.<o:p></o:p>