Can roommate sue ME for sec. deposit?

A friend and myself moved into an apartment together. We are both on the lease, and we split the security deposit.
She got a money order and her name was on it, and we gave it to the landlord.
We agreed to have my sister move in shortly after. Recently they've gotten into arguements and my sister tried to fight her after my friend began insulting her.
Litter appeared in my toothbrush, my sisters toothbrush, and all over my sisters clothes. So I told my friend to leave by friday.
WHile I was gone my sister broke down her door and put all oF my friends belongings back into her room. I found the litter and left my friend a note stating that she needed to leave by friday because she's putting litter all over everybody's things and she wanted all her stuff in her room so we did it for her.
She called the cops, and even though i didnt break into her room, because I put 'we' on the note, (like an idiot), I am getting charges pressed.
Now she is talking about how she's moving out and is going to go to small claims court to get the security deposit back from me if the landlord wont give it to her.
Considering all that has happened, does she have a case?

Your friend and you got the apartment together. Later another person moved in. You have no right to ask your friend to move out. It is as much her place as it is yours. She has every right, as the original lease holder, to ask your sister to move out.

I don't understand how her things got out of her room, or why you would break down her room door to put them back in. If she took her things out of the room, you or your sister shouldn't have touched them. Now that you have claimed, per your note, to have moved her belongings, she can sue you and your sister for several things. One, for making her move out since she was one of the two original lease holders (she has the right to stay). Forcing her out is a constructive eviction and is illegal. Two, for moving her stuff (possibly damaging her belongings, or having some of them come up missing). She can claims things are damaged or missing and sue you for the value of them. Three, for causing damage to the unit for which she will be charged. This will be covered by the deposit, which she paid the LL. It should come out of your half of the deposit.

I didn't break down her door or anything, I wasn't even home when it happened, I did ask her to leave, but she didnt. She is still here.
We actually found her heroin bags in the trash today and the police could not do anything because they were empty.
I don't really care if the damage to the door comes out of my half of the security deposit, I was just wondering if she could sue me for the entire security deposit.
Her things were in the livingroom. She put them there.
My sister has agreed to explain to the officer that she did everything and the officer said once she talks to him I won't be held responsible for what I didn't do.
However, now she's talking about she wants a thousand dollars of the security deposit?
I don't have her security deposit the landlord does.
And the only thing missing from her room was a hair dryer.
I doubt a hair dryer and a door cost a thousand dollars.

Tell her yu don't have her deposit, the LL does. She will need to contact him about the deposit. He probably won't turn it over since the unit isn't vacant and there could be other damages in there he wouldn't see.

Your other option is to repay her deposit with an amount equal to one half the deposit put up by your sister (and new roommate). The new roommate should have to put up a deposit too and that amount could be paid to the ex-toommate to get her out of the picture. Get a signed statement from her (if you do this) to give to the LL which states that she no longer has any interest in the deposit he's holding, and that it should be paid to you and your sister upon move out.