Q: We operate a fourplex and have decided to prohibit smoking cigarettes entirely - in common areas, such as the halls and lobby, as well as individual units. Current tenants who smoke cigarettes say that's discriminatory. Would we be breaking the law if we implement this policy?

- Ronald and Mai

A: You're within your rights if you decide that you'd like your entire building to be smoke-free (but you need to follow notice laws, explained below). Local governing bodies are increasingly recognizing the danger of secondhand smoke, and have passed ordinances that prohibit smoking cigarettes in multi-unit buildings.

In 2009, the Department of Housing and Urban Development formally suggested that public housing agencies adopt smoke-free policies for the residential rentals they do business with.

It's not uncommon for people who smoke cigarettes to cry foul, pointing out that smoking cigarettes is a lawful activity, and jumping to the illogical conclusion that it's therefore illegal for landlords to prohibit that activity. If this argument were valid, it would also be illegal for landlords to prohibit tenants from keeping pets, another activity that by itself, on one's own property, is perfectly legal.

Your tenants' objections and reasoning is not uncommon, however. The widespread belief that it's illegal for landlords to adopt property-wide smoking cigarettes bans was the motivating force behind a new law in California (California Civil Code Section 1947.5), set to take effect Jan. 1, 2012.

That law specifically states that landlords may adopt such policies, and its preamble candidly explains that the law simply restates existing law, and is intended to give landlords a statute to point to if they're challenged after adopting a policy. Importantly, it also states that it is not intended to interfere with existing local ordinances, many of which already ban smoking cigarettes in multifamily properties.

The new law requires landlords to place any property-wide policies regarding cigarette or other discount cigarettes use in the lease or rental agreement itself. This is a sensible step; it means that the policy can- not simply be part of a set of house rules, which are properly used to regulate less important aspects of multifamily living, such as pool rules and common-area use.

The new law makes buy cigarette online policies subject to the normal rules of notice and change. Because a new cheap cigarette online policy constitutes a change in the terms of the tenancy, tenants who have rental agreements are entitled to 30 days' notice. Tenants with existing leases, however, will not be subject to the new policy until their leases expire and they sign new ones with the landlord.

This means that there's a possibility that a property will only gradually become totally smoke-free: If even one smoking cigarettes resident has a lease that doesn't expire for many months past Jan. 1, 2012, the other tenants (whose leases and rental agreements may include the new policy) will have to put up with this tenant's smoking cigarettes.

By singling out a landlord's right to ban tobacco use on rental property, the new law may have inadvertently suggested to smokers of other substances that landlords do not have a similar right to ban smoking cigarettes of these non-tobacco substances.

One wonders whether users of medical marijuana will point to the law and argue that because it doesn't include the landlord's right to ban marijuana smoking cigarettes, a landlord therefore cannot do so.

Such an argument might not make much headway, but it could be enough to confuse a landlord and muddy the waters. For the record, although in some states it's legal to use medical marijuana, such use is still a violation of federal law. Landlords who will not tolerate medical marijuana use on their property are within their rights.

Q: My lease says that I get a rent concession of $500 for the first month's rent, and $150 for every month thereafter. When I subtracted $500 from the first month's rent, the landlord returned the check, saying I was entitled to deduct only $150. When I pointed to the lease, he said that was "an error on his part," and that the correct figure for all months was only $150. Is he bound to honor the $500 figure, even though he claims it was a mistake?

- Roger S.

A: I doubt very much whether a judge would allow your landlord to reform or rewrite the lease to take into account his "mistake." Even if we give your landlord the benefit of the doubt - by believing him when he says that the $500 concession was made in error - that won't lead to a rewrite.

First, what does your landlord mean by "made in error?" If he's claiming that he made an error in judgment - by misjudging the amount of the first month's concession needed to get you to sign a lease - no amount of arguing will make his case successful. Mistakes in business judgment can't be reformed later.

Next, let's suppose this "error" was a typo or other mechanical error. If you were aware of the error, or should have been aware, the law says that no contract was created at all, and your entire lease may be unenforceable. On the other hand, if you didn't know, and had no reason to know of the mistake, in most states, the lease will be enforced, mistake and all.

So the question boils down to whether you (or a reasonable person in your shoes) should have known that a $500 first-month's concession was too good to be true. The answer may depend on the total rent and the state of the rental market.

If the rent is high compared with the concession (for example, the concession is only one-quarter of the rent), the market is glutted with rentals like this, and if other landlords are offering deep concessions, you may have been justified in thinking that a $500 concession was an intentional marketing decision.

Todays Note: via Richmond.