The death of the 17-year-old African-American teen on Feb. 26 by neighborhood watch captain George Zimmerman in suburban Orlando, Fla. has ignited a debate about race, self-defense and Florida's "stand your ground" law.
In an interview on CNN's "State of the Union" Cosby said "when a person has a gun sometimes their mind clicks that this thing will win arguments and straighten people out and in the wrong hands and wrong mind, it's death, it's wounding people."
He said he wasn't opposed to people having guns in their own homes, but not on the streets.
Cosby added "when you tell me you're going to protect the neighborhood that I live in, I don't want you to have a gun. I want you to be able to see something, report it and get out of the way. Because you are part of the neighborhood I don't want you to get hurt and I don't want you to hurt anyone."
According to 911 tapes from the night of the incident, Zimmerman told the 911 dispatcher that he was following Martin and continued to do so even though the dispatcher told him to stop.
Cosby said he used to own a gun but no longer does, according to the Associated Press, and that people should be taught to use every possible alternative before shooting someone.
Cosby told NBC the real issue is "about guns in our country," why Zimmerman had a gun, and who taught him how to use it.
"When you have a gun, you may not realize it, but you put it on your person and you mean to pull this," Cosby told NBC's Meet the Press, motioning with his trigger finger, "and kill somebody. That's what you mean to do."