Probably. It's not clear whether the landlord's request for additional (double) deposit amounts to discrimination. However, the landlord's requested deposit must not exceed what is permitted by law. California Civil Code Section 1950.5(c) limits the total amount that the landlord can require you to pay as a security deposit. The total amount allowed as security depends on whether the rental unit is unfurnished or furnished and whether you have a waterbed.
Unfurnished rental unit: The total amount that the landlord requires as security cannot be more than the amount of two months' rent. If you have a waterbed, the total amount allowed as security can be up to two and-a-half times the monthly rent.
Furnished rental unit: The total amount that the landlord requires as security cannot be more than the amount of three months' rent. If you have a waterbed, the total amount allowed as security can be up to three-and-a-half times the monthly rent.
Plus first month's rent: The landlord can require you to pay the first month's rent IN ADDITION to the security deposit.
i think there might be some issues about whether their insistence on doubling the security deposit is a form of discrimination. I just don't see the legal justification for requiring twice the security deposit when a family member asks to be added to the lease. First of all, is it even nececessary to add your father - a family member - to the lease. I have some problem with the landlord's policy.
The housing discrimination does not require there to be an actual intent to discriminate. All that is required is that the rental policy has a disparate impact on a particular protected group - persons with disability is one such group. The protection against discriminaton is braod.