The Orange Box

In the chapter Point Insertion, a cop will knock a soda can off of the side of a trash bin. Here you have two choices. You can listen to what he says, and throw the can in the garbage, earning the Submissive achievement. Your other option is to throw it at him, and get the Defiant achievement.

When the combine police officer makes you throw the can into the bin, throw it at the police officer.

Also if one saves before doing this then you can also get the submissive achievement.

When approached with the guard who knocks the can down at the beggining of the game pick up the can and press RT to throw it back at him.

This achievement is very easy, and you can get this achievement and the Submissive achievement very easily. In the first chapter of Half Life 2 (not episode 1 or 2, just Half Life 2), and shortly after you begin your game, do as it asks and go where it leads you. Eventually you will get to a point to where you have to down a hallway but will be stopped by a officer. The officer will knock over a can and ask you to throw it away. And if you want to get both achievements here then save before you do anything after reaching that point so that you can go back later and do what the cop asks. Now all you have to do is pick up the can ( X ) and press ( RT ) when looking at the cop with the can in hand to throw it at him, after that the achievement should be unlocked. And to get the other achievement you can reload the save you made before and instead of throwing the can at the cop, do as he asks and drop it in the trash can by again, picking the can up using ( X ) and dropping it in the garbage can pressing ( LT ). After doing that the other achievement should be unlocked as well.