spouse going after everything

I live in ca. I am separated from my husband of shortly over 10yrs.
He has retained an attorney and is going after my pension,401k, etc. and wants me to pay half of his income tax debt.
From the outset of our marriage I filed married, separately. He is in self employed and is claiming to make under 20,000 a yr. Five yrs. ago I found out he was not paying his taxes.( at that time I urged him to contact the irs and straighten it out with them) subsequently I have learned he owes 15,000 to irs during the 10 yrs. of marriage. Can I be responsible for his debt?
Thank you

No, you are NOT responsible for it! The ONLY way they will hold you responsible is IF you filed jointly! I know, my ex spouse did the same thing, for 7 years! To the tune of anywhere between 75K-150K per year! Thankfully I never filed joint with him because he never filed! Even though he told me his "accountant" was taking care of "things." Also, one more thing do yourself a favor. Go online and print your family code, this will give ALL the can & can'ts in a divorce decree. Most people feel the divorce decree is the last word. It isn't. The family courts have no say in federal or civil matters, which boils down to a divorce decree that should only be 2 pages long. In Texas (which is where I'm from) the ONLY thing you can go back to court for contempt of court is, Child support, visitation, alimony and division of property, and the property has a limit of I believe 2 years from the final date of divorce. I could write a book on what to look for when it comes to divorces! I NEVER trusted my attorney, they are in it for the money, remember they don't care about you, you MUST take responsibility for YOURSELF and PROTECT yourself! When divorcing, make sure all credit cards, (joint or authorized user is closed!), and any property SELL IT! You will still be held liable for the payments regardless what the divorce decree says. Oh yes, one more thing, if your soon to be spouse has not filed taxes for x amount of years and the IRS hasn't caught up with him, you can report him for tax evasion, the give a finders fee of 15% to what is recovered, it may take years to see it, but hey. Good Luck!

thank you so much txtornado for your response. I feel relieved (as much as one can be in a divorce situation) In a community state such as ca. he will in fact get a portion of my pension, 401k, etc., not to mention a percentage of my social security. He didn't pay in to the system for yrs.
I just do not want to lose my house which was my sole property before the marriage but became community property during the 10 yrs. of marriage. Upon our separation ,I refinanced my sole property and gave him 20,000. We signed an agreement that he would not come back later for anything and that it was a final settlement. This was notorized and signed by both of us. His attorney claimed it was not legal because there was no disclosure of assets. He filed for a motion to set aside the agreement which the judge did. He claimed he does not have the 20,000 to give back. The judge ruled that the 20,000 will be on record. Can the courts let one get a way with taking ones assets? He did not keep records, checking, savings, everything was mainly on a cash basis. What will I get legally?
He did not even submit anything during the "declaration of assets" process except for his truck and tools.(which he said he needs for his seasonal work) His attorney wrote it was burdensome...in return I had to submit everything for up to 2 yrs.
All my assets were documented, income tax returns, paystubs, checking and savings accounts, etc. etc.
He is even claiming that the money I got back from my income tax every year was community property and he is entitled to a portion of it?
Do you think the judge will see through this tactic??
Prenup, prenup, prenub...my new motto!!!!