The use of Pathos was evident in the first paragraph where the writer compliments the congressman of his past voting records. In the second part of the paragraph, he appeals to the congressman as a concerned parent who lost his child, so he's appealing to the congressman's emotion of worry.
In the second paragraph, the writer uses Logos as he states statistics of the number of people dying every year due to gun shots. At the last part, the writer says "it is much higher now" giving the congressman the impression that the number has shot up to an extraordinary number which gives him a reason to fear. Here the writer uses Pathos again.
In the third paragraph, The writer once again uses Logos by presenting facts about the use of guns and where there are bought from, whether there are legally or illegally bought. Through this, he also shows Ethos, showing the congressman his knowledge of guns in the black market.
In the fourth and fifth paragraph, the writer uses Logos again and presents the data. He also uses Ethos to show how much he knows about the subject.
In the sixth paragraph, he uses Pathos by asking the congressman rhetorical and emotional questions. "Do you want to be responsible for supporting legislation that would make more such incidents occur?" These questions, although rhetorical, questions the congressman decisions.
In the last paragraph, he questions the congressman's decision again and says what he's doing will have an impact on the whole country.