And all the people said "Duh!"

That's a somewhat...well....dumb statement...IF he really said that...and IF it was printed in context. (Note that the article doesn't really say or explain anything.)
The odds of a police officer being present at all the places where a murder occurs (mostly private homes)...extremely unlikely. People who get arrested and put in jail get out on bail or bond. The only alternative is if someone gets arrested...never, ever let them out...that way they can't commit more crimes in the future...right? See the silliness in his statement?
I'm not saying the city doesn't need more officers, but more officers would not likely affect the murder rate since people usually wait until there's a police officer NOT around before they murder.