Analyze vs. Advocate

On a bar exam essay, be the legal analyst that Fox News or MSNBC, or Choose Your Favorite News Channel, brings on the show to explain to the viewers what both sides of the legal issue are likely to argue. You're the analyst, the graders are the viewers at home watching.

"The store is likely to claim that it wasn't false imprisonment because it acted reasonably in detaining for a short period of time, etc., etc." But the customer will respond that although the store had the right to ask the customer to return the merchandise, it did not have the right to etc., etc." To that, the store might respond that..." Eventually you'll come to the conclusion of the IRAC and that's a good place to give your opinion or to advocate for one side. But don't be so definite in that conclusion/opinion unless certainty is absolutely warranted. 

I should note that this is just the view of one person (me) who has read many bar exam essays and has developed a philosophy based on feedback I've seen given from graders. Still, it's an opinion, and opinions may vary. I can only give mine!