Fowler taking the gun from tyrese? Spoilers

I actually enjoyed this movie. A friend of mine made me go see it when it came out and I didn't expect much but was pleasantly surprised. Good kick ass brothers movie. Don't expect every movie you be the godfather. I enjoy certain movies for what they are. But anyway one thing that I was always curious about is at the end with their big plan. The scene when tyrese takes the dirty cop Fowler hostage and his girlfriend tells the cops that her boyfriend is going to kill a cop so all the cops show up. The plan was to make Fowler look like the bad guy. So was the plan to actually make Fowler take the gun from tyrese and bring him out for the cops to see ? What if he didn't take the gun? What other way we're they gonna show that Fowler was dirty?