Bunnies should definitely be kept inside. They live longer, are healthier and develop their little bunny personalities when they are able to bond with their human. Bunnies love to play, love to be with their people, and are quite the comedians. You don't see any of this if they are left outside and you only spend a few minutes a day with them.

However you should also know that they are a lot of work when kept inside. You need to bunny proof the room they will be in. They need litter boxes (yes, several). They get easily bored and will need toys to keep them amused. It can be something as simple as an empty topilet paper roll, an empty margarine tub, an old telephone book for digging up and tearing (they love that sound for some reason). These are good toys for cages too. The most important thing is that the bunnies be trained to use a little box. Personally I have found out that the bunnies do this pretty much for themselves. The trick is putting the litter boxes where THEY, not you, want them. You may need only one litter box, but most bunny owners will tell you you will need several. And you will need to stay on top of the boxes clean or the buns won't use them after a while (plus the room would smell...yuck!) The referral to the House Rabbit Society's web page was a good one and they have all kinds of expert advice in there on health nutrition (almost NO pellets should be given), and things like litter training.

Basically it comes down to how much time you are willing to spend with bunnies and what your stepdad and your mom will allow. Maybe if you build a strong enough case to show that you've researched bunnies living inside vs bunnies living outside, (like checking out the HRS web site and others) that might help you convince them. Just remember they need more care and attention if they live inside. Some of us let our bunnies have their very own room, while some bunny owners keep their buns in cages when they aren't home and then let the bunnies out for play time....there are several diff. ways to keep a bunny in the house.
Good luck with researching and making your decision about where they should live.