First, it's surprising that you would pose this question if you were actually already appointed as the property management guardian for your mom pursuant to Article 81 of the Mental Hygiene Law, since I would expect that you would be represented by an attorney in that proceeding. If you represented yourself in such a proceeding, you must either have had a very good working knowledge of Article 81 or an extremely supportive Judge and Court Evaluator.
In any event, if you were appointed guardian, then you likely have already finished the certified guardianship training. And one of the things that you would have learned is that all assets must be held by you in your capacity as guardian.
Thus, if you are shifting assets from one vehicle to another, you would be required to maintain the funds in an account entitled, "________ as property management guardian for _________, an incapacited person" or something of like effect. This could be accomplished by either retitling the investment account or by opening a new guardianship account.
You cannot take assets from the investment account and place them in your mom's joint account. Not only would that be improper and not only would it likely violate the terms of the order and judgment appointing you and the commission of guardian, but it would pose a variety of difficulties when you do your interim account and any of your annual accountings. Worse yet, it would likely yield skewed results as to what would arguably be in your mom's estate at such time as she passes away.
As you likely know, a joint account has a right of survivorship, such that any assets in the account vest in the surviving joint tenant at the time of the other accountholder's death.
You don't say who the other joint tenant is of the account, but the point is that you need to do things properly. There can be a variety of unintended, and decidedly negative, results if you do not do everything properly.
Your best bet is to get an attorney involved. It should be someone with substantial experience in guardianships, and, in any event, someone who knows about the interim accounting that you must make shortly after qualifying as guardian; someone who knows about the annual accountings that must be filed, usually in May of each year for the preceding year; knows about how to do annual accountings; and can advise you as to how to procure a surety bond, if this was required by the court.
If you would like, you may feel free to contact me -- I have done more than 200 proceedings that relate to guardianships. Or, there are many attorneys here on avvo who can be of help to you.
Good luck to you.
Michael S. Haber is a New York attorney. As such, his responses to posted inquiries, such as the one above, are limited to his understanding of law in the jurisdiction in which he practices and not to any other jurisdiction. In addition, no response to any posted inquiry should be deemed to constitute legal advice, nor to constitute the existence of an attorney/client or other contractual or fiduciary relationship, inasmuch as rendering legal advice involves the ability of the attorney to ask appropriate questions of the person seeking such advice and to thus gather appropriate information. In addition, an attorney/client relationship is formed only by specific agreement. The purpose of this answer is to provide the questioner with general information, not to outline specific legal rights and remedies.
Additional information is needed (ie who froze the account and under what authority). Either way what you would need to do is petition the court and have yourself (or someone else you trust) appointed her guardian. Once that happens you would have full control to do with her assets as you determine to be in her best interests. You may wish to consult with an attorney who can assist you through the process.
You will need an order from the Guardianship judge directing the transfer of the account into a guardianship account. You should consult with the lawyer that helped to get you appointed guardian.
Unless specifically stated otherwise, this communication shall not be deemed to be legal or tax advice, and no attorney-client relationship shall be deemed to have been created.