In the first paragraph, pathos is used. Pathos is used when he says he is a concerned parent who lost a child due to a gun accident and also compliments the congressman who he was talking to.
In the second, third, fourth and fifth paragraph, he uses logos and talks about data and statistics to convince the congressman on is knowledge in the field.
In the sixth paragraph, he uses pathos once again as he tries to explain his interest in the topic which was the fact that he lost his child due to a gun accident and asks a rhetorical question that might make the congressman think twice on supporting the legislation.
In the last paragraph, he uses ethos and logos by talking about deaths due to the fact that guns were readily available.