Those who've followed the news of San Francisco's very lax position on immigration, the types of people who promote massive immigration, as well as our Obama citizenship issue might get a chuckle (or more) out of this. If you aren't familiar with those issues, see the points below. From the last link:

San Francisco's transportation authority has adopted a plan to issue special street parking permits to nannies, after a group of parents complained that current parking restrictions pose a safety risk to kids.

...Parents seeking a childcare-provider permit must collect signatures from half of the households on their block, the San Francisco Examiner reports. They also must show a birth certificate proving that at least one child in the household is age 12 or younger.

1. There are a relatively small number of people who professionally promote or enable massive immigration, and many of those are in what's been called around here the "Nanny Employing Class" ("NEC"). (If they move up the economic scale, they become part of the "Greenskeepers Employing Class"). Members of both classes support massive/illegal immigration in part due to completely selfish reasons: they want a large pool of inexpensive, pliable help whether on their homes, their gardens, or the like.

2. No doubt much of the support for San Francisco doing things like ignoring the immigration status of those arrested comes from the very same NEC; there aren't too many chicken processors or strawberry farms in San Francisco, but no doubt a fair number of illegal aliens work as nannies or other types of household help. While those in the NEC would be willing to turn over a birth certificate showing a child was born after a certain date, about the last thing they'd want to do is have the government verify that someone they're hiring was born here or is here legally.

3. And, of course, no doubt the vast majority of San Franciscans are of one mind on the "Birther" issue: the vast majority probably think Obama doesn't need to show his birth certificate or that a picture on his website is the same as a birth certificate.