Your situation involves a lot of different legal issues! Just your luck that it is so complicated. You have union issues, FMLA issues, FEHA/ADA issues (because extended leave can be a reasonable accommodation under law), workers' compensation issues and perhaps more. Not surprisingly, you will need to consult with one or more experienced employment law attorneys with whom you can discuss the details of your situation. There is no realistic way to address all this here on a Q & A board such as Avvo.
But to answer your direct question: Yes, you can be terminated while on medical leave but you cannot be terminated BECAUSE you are on medical leave, at least not under many circumstances. There are various sources of POTENTIAL protection related to your medical status.
If the condition is due to a disability as defined by law, the Americans with Disabilities Act of 1990, 42 U.S.C. sections 12101 et seq. (ADA) and the California Fair Employment and Housing Act, California Government Code sections 12900, et seq. (FEHA) may provide some protection. Please look at my guide on the ADA: http://www.avvo.com/legal-guides/ugc/employment-disability-protection-under-californias-fair-employment-and-housing-act-and-federal-ada and also on the differences between the ADA and California’s more generous FEHA: http://www.avvo.com/legal-guides/ugc/employment-disability-protection-under-californias-fair-employment-and-housing-act-and-federal-ada?published=true. The ADA applies to employers with at least 15 employees; the FEHA requires only 5 employees. These laws protect you from discrimination (adverse treatment) DUE TO disability and also require the employer to provide reasonable accommodation (change in the manner in which work is done) so you can do the main parts of the job (essential functions). A leave of absence can be a proper reasonable accommodation.
There is limited protection if the illness or injury is caused by a serious medical condition as that is defined by law. You may be protected under the Family and Medical Leave Act, 29 U.S.C. section 2101 et seq. (FMLA) and the California Family Rights Act, Government Code section 12945.2 (CFRA) if all of the following is true: (a) your employer has at least 50 employees who work within 75 miles of one another; and (b) you have worked for this employer for at least one year all together, even if not consecutively; (c) you have worked for this employer at least 1,250 hours in the immediately preceding year; and (d) you have a serious medical condition as defined by the FMLA. The FMLA allows employees to take leaves of absence from work without repercussion, up to a maximum of 12 weeks per year. Leave can be in increments as short as fractions of an hour.
Please look at my guide on the Family and Medical Leave Act, 29 U.S.C. section 2101 et seq. (FMLA) to see if that law applies in your situation: http://www.avvo.com/pages/show?category_id=6&permalink=family-and-medical-leave-fmla-summary-of-key-provisions. California’s CFRA is the same as the FMLA in all areas other than pregnancy disability and enforcement.
Finally, if the condition is due to on-the-job injury, is caused by work or is made worse by work, California’s workers' compensation laws may provide some relief. To find a workers' compensation attorney, please look at the membership list of the California Applicant Attorneys Association (CAAA) http://caaa.org/cs/. CAAA is the strongest bar association in California for attorneys who represent injured workers.
Your rights under each of these three laws are independent of one another. That is, you may be entitled to protection from each of these laws at the same time.
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twitter.com/MikaSpencer *** All legal actions have time limits, called statutes of limitation. If you miss the deadline for filing your claim, you will lose the opportunity to pursue your case. Please consult with an experienced employment attorney as soon as possible to better preserve your rights. *** Marilynn Mika Spencer provides information on Avvo as a service to the public, primarily when general information may be of assistance. Avvo is not an appropriate forum for an in-depth response or a detailed analysis. These comments are for information only and should not be considered legal advice. Legal advice must pertain to specific, detailed facts. No attorney-client relationship is created based on this information exchange. *** Marilynn Mika Spencer is licensed to practice law before all state and federal courts in California, and can appear before administrative agencies throughout the country. She is eligible to represent clients in other states on a pro hac vice basis. ***
Yes your employment may be terminated while out on FMLA leave IF the reason is not because of your medical condition or any other protected class (age, race, religion, pregnancy, gender, etc.) And FMLA only protects your job for up to 12 weeks.