In CA, there is both community property and separate property, along with community obligations and separate obligations. According to the following statute:
770. (a) Separate property of a married person includes all of the following: (1) All property owned by the person before marriage. (2) All property acquired by the person after marriage by gift, bequest, devise, or descent. (3) The rents, issues, and profits of the property described in this section. (b) A married person may, without the consent of the person's spouse, convey the person's separate property. 771. (a) The earnings and accumulations of a spouse and the minor children living with, or in the custody of, the spouse, while living separate and apart from the other spouse, are the separate property of the spouse. (b) Notwithstanding subdivision (a), the earnings and accumulations of an unemancipated minor child related to a contract of a type described in Section 6750 shall remain the sole legal property of the minor child.
The date of Physical Separation is important because generally the court will treat any property/debts acquired after the date of physical separation as the property/obligation of the party acquiring/incurring them. While CA does have a process for filing for legal separation, the court will use the date of physical separation for determining assets/obligations.
As for obligations incurred during the marriage, the community is liable; and generally these are divided in half. However, the creditor can go after either spouse as they are "jointly and severally liable" for the debt (meaning one party can be required to pay the full amount, but can sue the other spouse for reimbursement of 1/2).
However, there is also a concept called fiduciary duty. The spouse that does not exercise utmost good faith and due care with community assets (and the separate property of the other) can be held accountable, and be required to reimburse the spouse for this. This includes money/assets spent on third parties.
The relevant statutes are below:
1100. (a) Except as provided in subdivisions (b), (c), and (d) and Sections 761 and 1103, either spouse has the management and control of the community personal property, whether acquired prior to or on or after January 1, 1975, with like absolute power of disposition, other than testamentary, as the spouse has of the separate estate of the spouse. (b) A spouse may not make a gift of community personal property, or dispose of community personal property for less than fair and reasonable value, without the written consent of the other spouse. This subdivision does not apply to gifts mutually given by both spouses to third parties and to gifts given by one spouse to the other spouse. (c) A spouse may not sell, convey, or encumber community personal property used as the family dwelling, or the furniture, furnishings, or fittings of the home, or the clothing or wearing apparel of the other spouse or minor children which is community personal property, without the written consent of the other spouse. (d) Except as provided in subdivisions (b) and (c), and in Section 1102, a spouse who is operating or managing a business or an interest in a business that is all or substantially all community personal property has the primary management and control of the business or interest. Primary management and control means that the managing spouse may act alone in all transactions but shall give prior written notice to the other spouse of any sale, lease, exchange, encumbrance, or other disposition of all or substantially all of the personal property used in the operation of the business (including personal property used for agricultural purposes), whether or not title to that property is held in the name of only one spouse. Written notice is not, however, required when prohibited by the law otherwise applicable to the transaction. Remedies for the failure by a managing spouse to give prior written notice as required by this subdivision are only as specified in Section 1101. A failure to give prior written notice shall not adversely affect the validity of a transaction nor of any interest transferred. (e) Each spouse shall act with respect to the other spouse in the management and control of the community assets and liabilities in accordance with the general rules governing fiduciary relationships which control the actions of persons having relationships of personal confidence as specified in Section 721, until such time as the assets and liabilities have been divided by the parties or by a court. This duty includes the obligation to make full disclosure to the other spouse of all material facts and information regarding the existence, characterization, and valuation of all assets in which the community has or may have an interest and debts for which the community is or may be liable, and to provide equal access to all information, records, and books that pertain to the value and character of those assets and debts, upon request. 1101. (a) A spouse has a claim against the other spouse for any breach of the fiduciary duty that results in impairment to the claimant spouse's present undivided one-half interest in the community estate, including, but not limited to, a single transaction or a pattern or series of transactions, which transaction or transactions have caused or will cause a detrimental impact to the claimant spouse's undivided one-half interest in the community estate. (b) A court may order an accounting of the property and obligations of the parties to a marriage and may determine the rights of ownership in, the beneficial enjoyment of, or access to, community property, and the classification of all property of the parties to a marriage. (c) A court may order that the name of a spouse shall be added to community property held in the name of the other spouse alone or that the title of community property held in some other title form shall be reformed to reflect its community character, except with respect to any of the following: (1) A partnership interest held by the other spouse as a general partner. (2) An interest in a professional corporation or professional association. (3) An asset of an unincorporated business if the other spouse is the only spouse involved in operating and managing the business. (4) Any other property, if the revision would adversely affect the rights of a third person. (d) (1) Except as provided in paragraph (2), any action under subdivision (a) shall be commenced within three years of the date a petitioning spouse had actual knowledge that the transaction or event for which the remedy is being sought occurred. (2) An action may be commenced under this section upon the death of a spouse or in conjunction with an action for legal separation, dissolution of marriage, or nullity without regard to the time limitations set forth in paragraph (1). (3) The defense of laches may be raised in any action brought under this section. (4) Except as to actions authorized by paragraph (2), remedies under subdivision (a) apply only to transactions or events occurring on or after July 1, 1987. (e) In any transaction affecting community property in which the consent of both spouses is required, the court may, upon the motion of a spouse, dispense with the requirement of the other spouse's consent if both of the following requirements are met: (1) The proposed transaction is in the best interest of the community. (2) Consent has been arbitrarily refused or cannot be obtained due to the physical incapacity, mental incapacity, or prolonged absence of the nonconsenting spouse. (f) Any action may be brought under this section without filing an action for dissolution of marriage, legal separation, or nullity, or may be brought in conjunction with the action or upon the death of a spouse. (g) Remedies for breach of the fiduciary duty by one spouse, including those set out in Sections 721 and 1100, shall include, but not be limited to, an award to the other spouse of 50 percent, or an amount equal to 50 percent, of any asset undisclosed or transferred in breach of the fiduciary duty plus attorney's fees and court costs. The value of the asset shall be determined to be its highest value at the date of the breach of the fiduciary duty, the date of the sale or disposition of the asset, or the date of the award by the court. (h) Remedies for the breach of the fiduciary duty by one spouse, as set forth in Sections 721 and 1100, when the breach falls within the ambit of Section 3294 of the Civil Code shall include, but not be limited to, an award to the other spouse of 100 percent, or an amount equal to 100 percent, of any asset undisclosed or transferred in breach of the fiduciary duty.
720. Spouses contract toward each other obligations of mutual respect, fidelity, and support. 721. (a) Subject to subdivision (b), either spouse may enter into any transaction with the other, or with any other person, respecting property, which either might if unmarried. (b) Except as provided in Sections 143, 144, 146, 16040, and 16047 of the Probate Code, in transactions between themselves, spouses are subject to the general rules governing fiduciary relationships that control the actions of persons occupying confidential relations with each other. This confidential relationship imposes a duty of the highest good faith and fair dealing on each spouse, and neither shall take any unfair advantage of the other. This confidential relationship is a fiduciary relationship subject to the same rights and duties of nonmarital business partners, as provided in Sections 16403, 16404, and 16503 of the Corporations Code, including, but not limited to, the following: (1) Providing each spouse access at all times to any books kept regarding a transaction for the purposes of inspection and copying. (2) Rendering upon request, true and full information of all things affecting any transaction that concerns the community property. Nothing in this section is intended to impose a duty for either spouse to keep detailed books and records of community property transactions. (3) Accounting to the spouse, and holding as a trustee, any benefit or profit derived from any transaction by one spouse without the consent of the other spouse that concerns the community property.
After reviewing the above, please let me know if you have any questions. Also the courts in CA have family law facilitators that will assist a self represented party in filling out the paperwork.