You don't state how old you were at the time of the arrest but if you were juvenile or very young (18 - 20 or so) it will probably give them good grounds to ask you some questions about your current views on theft, but not automatically exclude you from consideration.

Bear in mind that theft is MUCH different from getting drunk and doing something stupid one night. They will take into consideration that you had to think about and plan how to get away with stealing as opposed to getting carried away and making a mistake in the process. You really need to consider how you're going to answer when they ask you about it. The answer should not only impress them that you have learned a HUGE lesson from this but it should also satisfy them that you won't be stealing from your arestees or from the department.

Don't forget that someone on your interview board might use this incident to provoke you into some sort of emotional bombshell. If they use a hostile interview technique they will be looking to see if they can goad you into an unstable outburst.