Is it legal for trustee of mothers irrevocable trust in california takes early distribution of $175,000 to refinance his own home?

As a beneficiary of the trust you are entitled to a report and account of  the acts of the trustee for the entire time that he served as trustee.  The California Probate Code provides that right and other rights to you as a beneficiary, including the right to challenge your brother for breach of his fiduciary duties to you as a beneficiary. One of those duties is the duty of impartiality, which requires, generally, that he must treat beneficiaries the same.  He cannot distribute funds to himself and refuse to distribute funds to you, for example. The final account and report due from your brother must meet certain requirements of the Probate Code, including providing you with schedules showing all assets on hand at the time of  your mother's death, all income receipts, all disbursements, all gains or losses upon sale of trust assets, all distributions, and the property on hand at the close of the account that is available to be distributed to the beneficiaries. When a trustee fails or refuses to provide information reasonably requested by a beneficiary, or fails to report and account, the beneficiary can enforce his rights by filing a petition in the probate department of the Superior Court in the county where the trustee resides. The court will issue an order compelling the trustee to serve on you and to file with the court the Probate Code compliant final report and account. You as a beneficiary would then be entitled to file Objections to the report and account with respect to any act of the trustee that was improper.  To the extent any of those actions of the trustee caused damage (such as loss of money) to the trust, the court can order the trustee to repay those damages to the trust. In some cases of wrongful taking of trust funds by the trustee damages may be doubled. You should consult an attorney who specializes in estate and trust litigation.  The trustee must give you a copy of the trust, if he has not already done so, and your attorney will want to discuss the facts in detail with you and review the trust to see if it changes any of the trustee's duties discussed above from what the law would otherwise require. That attorney can first make written demands to the trustee on your behalf which will either produce the desired result or form the basis for a petition to the court if the trustee still fails to respond.