If your sister had been completely barred from your father's home and she did this without his permission at all or the permission of the person who had the POA at the time that this happened, then you can contact the local police department regarding a claim for criminal trespass and breaking and entereing -- because she did not remove any valuables (while a will is valuable, it is not like removing jewelry or money), there are really no criminal theft charges here that I can see based upon the actions that your sister has admitted to. Now, whether or not any criminal charges will be pursued will be completely up to the local town or county police authorities -- you may go to them with this information and copies of the deposition to show that she admitted to doing these things, but they may decline to look into the matter or even if they look into the matter, they may decline to prosecute her for anything and decide that what occurred is really a private family matter and they may tell you to pursue remedies in civil law (such as a lawsuit for civil trespass and invasion of privacy) or estate law (such as pursuing the will in probate court and making certain your sister is completely cut out as your father intended). When members of the general public approach the police department in this manner we can never be completely certain that the police or the DA's office will want to assist and pursue the matter criminally against the offending person and the discretion always lies with those authorities on what to do here. You could end up with a situation where the police do get involved and then your sister states that your father never told her she was not to enter his house or he never specifically barred her from going into the house and if no one can state that your father actually did this in their presence or the father told them that your sister was forbidden from entereing his house, then the police may decide that she had as much right to go into the house as the rest of the children (so there was no trespass). So, my suggestion is that you contact the local police authorities and tell them everything you have stated here and even suggest to them that what she did is criminal trespass and breaking and entering into rooms and cabinets where she did not belong and did not have your father's permission or the permission of the POA. I was a prosecutor for a few years and I have seen cases and claims like this go in both directions -- sometimes the police will pursue it and sometimes they will not depending upon time passed since the incident, seriousness of the incident and what the overall situation and dynamic happens to be and you will not know if they will even contemplate prosecuting this until you actually speak to an officer or a detective about these matters.
I wish I could give you a quick and easy answer on this but it is really a discretionary call on the part of the officers and the DA. While what she did is outrageous to your family and offensive to your father and his memory, criminal prosecution is completely in the hands of the police and ultimately the DA.
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