What a sad situation for you and your family. As you are probably aware, a LPS Conservatorship is for an individual who are gravely disabled and unable to provide for any of her/his basic needs. It certainly sounds like your sister should be under an LPS Conservatorship. However, only designated mental health facilities, state or county agencies or the courts can make referrals to the Public Guardian to initiate this process. Your sister must have a primary mental health diagnosis and be assessed by the designated facility as needing this type of conservatorship.
You can start by speaking to the facility where your sister is to find out if they will be referring your sister to the Public Guardian for the purposes of pursuing an LPS Conservatorship. It would be in your family’s best interest to meet with a Probate attorney who is knowledgeable in this area. An attorney can guide you through the process and with ensuring that your family is protected, as well.
Since you indicate that you are in Van Nuys, I am attaching a link to Los Angeles County Department of Mental Health’s website for some additional information. I hope this helps you. If you have any additional questions, please add them in the “comments” section.
Disclaimer: The above answer does not create an attorney/client relationship. My responses are intended to provide general information about the question posted. I am licensed to practice in the state of California. The information provided on this site should not be used as a substitute for conferring with or hiring a competent legal advice from a licensed attorney that practices in the subject area in your state.
LPS conservatorships are generally petitioned for by the public guardian or the entity that is holding your sister. If she is in a psychiatric ward it is likely that emergency protective orders have already been issued. LPS Conservatorships must be renewed annually and are confidential matters. It might be better for all of you to let the hospital or the public guardian handle it.
Involuntary is the key here. Your sister is entitled to a trial by jury if she disagrees with the appointment of a conservator. Thus, your mother cannot force her into it. The county has to take the action.