What possible charges can be brought up for withdrawing funds from a trust illegally?

Petty theft, grand theft, fraud, and embezzlement are a few that come to mind. These are all criminal charges. Breach of fiduciary duty is a civil remedy which could be used as well.

Your question can not be answered because you have not included enough facts. The position of the person doing the withdrawals must be known. Further if you wish to know if the matter can be prosecuted criminally you need to seek the counsel of a criminal attorney or file a complaint with your local district attorney.

If you feel a trustee has wrongfully withdrawn funds you should first file a petition in court to have the trustee removed and held liable for his actions. Depending on the severity of the conduct and the amount of money, you may be able to get a District Attorney to file criminal charges for fraud or embezzlement. But normally these issues are handled in Probate Court.