Legal Question in Real Estate Law in California

No. If a contract is held by a court to be null [never existed in fact] or void [existed but ruled not to be binding], it means it is as though no contract ever existed. The failure to pay rent is a breach of the rental contract entitling the landlord to damages; the lease still exists and you are subject to the terms of the lease. So if you have a one year lease and yo are evicted after 6 months, you are still responsible for the remaining 6 months of the lease,but the landlord has a duty to mitigate [reduce] his damages be reasonably trying to find someone to rent the property.

I don't disagree with Mr. Shers, but there is something else that may need explaining. When a lease is breached, the landlord often has the option of declaring a forfeiture. Then, even if you correct the breach by watering the lawn, getting rid of the dog, or whatever, the balance of the lease remains forfeited and you can still be evicted. See Code of Civil Procedure section 1161, paragraph 3. Forfeiture of the lease is an option for many kinds of breach, but not for nonpayment of rent (as I understand the law). So, maybe when you ask about the lease being null and void, what you are really asking is whether the lease is forfeited. The answer is, I think, that if the only breach was a non-payment of rent, and the breach is cured by later payment, the lease cannot be forfeited and remains in effect.