Actress Daryl Hannah and other celebrities have been protesting the planned removal of squatters who for over a decade have maintained an "urban garden" on an LA property that the owner wants to turn into a warehouse. If the protest succeeds, it is likely to achieve the opposite of its intended goal. By saving this one garden, the protesters are likely to make "urban gardens" more difficult to establish in the future.

The relevant facts, according to CNN:

LOS ANGELES, California (AP) — Sheriff's deputies evicted people from an urban community garden to make room for a warehouse Tuesday, touching off a furious protest in which actress Daryl Hannah and others climbed into a walnut tree or chained themselves to concrete-filled barrels. At least 39 people were arrested.....

About 350 people grow produce and flowers on the 14 acres of privately owned land, in an inner-city area surrounded by warehouses and railroad tracks. The garden has been there for more than a decade, but the landowner, Ralph Horowitz, now wants to replace it with a warehouse.....

Horowitz accused the farmers of ingratitude, saying they had sued him and their supporters had picketed his home and office.

"I feel that the gardeners have been on the land for 14 years, almost 15 years for free. After 15 years, you say thank you," he said.....

The effort to save the farm attracted the support of activists and celebrities including Hannah, environmental activist John Quigley, country singer Willie Nelson, actor Danny Glover, folk singer Joan Baez and tree sitter Julia Butterfly Hill.

I think that Hannah and the other celebrity protesters have not thought the issue through as well as they should have. If they get their way, they might be able to save this particular garden. But if landowners such as Ralph Horowitz learn that once you let people garden on your property, you in effect lose your rights and can never remove the garden, they are likely to refuse to allow the creation of urban gardens on their land in the first place. This is especially likely if the government forces the owners to allow such gardens to stay in place permanently, once established. But even if the authorities merely let protesters such as Hannah & Co. usurp the owner's rights through private action, the same results might occur. Whatever one thinks of Mr. Horowitz, he did permit the garden to stay on his property for over a decade. It is unlikely that he and other similarly situated owners would do so if they had thought that it would lead to the permanent loss of their property rights.

To be sure, the government could (setting aside Takings Clause considerations) simply require owners to allow the establishment of urban gardens on any urban properties where local activists would like to plant them. But in addition to being a serious violation of property rights, this approach would severely undercut incentives to invest in urban property, thus imposing major economic costs on urban areas.

UPDATE: I have removed a "[sic]" that I mistakenly inserted in the CNN quote.

UPDATE #2: Contrary to the implications of the CNN story, this article by LA Times columnist Steve Lopez suggests that the Horowitz did not consent to the use of his property by the squatters. The land was condemned by the city in the late 1980s in order to build a sewage plant. After the plan to build the sewage facility was scuttled by political opposition, Horowitz managed to get the property back in 2003, following prolonged litigation. He then began his efforts to remove the squatters (who had started the urban garden during the period when ownership of the property was under dispute between Horowitz and the City) so that he could build a warehouse. Whatever the facts of this specific dispute, however, the main point of the post is still valid: if property owners know that they are not allowed to remove "urban gardens" from their land, they will be extremely reluctant to allow them to be established in the first place.

UPDATE #3: A few additional reasons why my main point holds despite the fact that the garden was initially established without Horowitz's consent. First, regardless of Horowitz's situation, other landowners do in fact sometimes consent to the establishment of community gardens on vacant property lots that they own. Obviously, they are unlikely to do so in the future if Daryl Hannah and her friends succeed. Second, even if the initial effort to establish the garden did not have the owner's consent, he is likely to try much harder (and much more quickly) to get rid of the garden if leaving it alone would lead to the permanent loss of his rights. Absent such a fear, the owner of a vacant lot might well find it cheaper to let the squatters stay until such time as he needs the land for another purpose than to take action against them. Finally, some owners could try to preemptively build structures on their vacant lots for the sole purpose of making it unsuitable for use by farmer-squatters. This would both make it more difficult to establish urban gardens and result in wasteful spending.