I live in Menlo Park, California. On 95% of the streets here you are
not allowed to park overnight (exact text of the ordinance follows). I
need specific legal strategies/precedents for challenging this law in
State or Federal court. 

My analysis is that the ordinance's darker intent is, and has been for
40 years, to keep Menlo's population in check by discriminating
against landlords, tenants, students, visitors, and large immigrant
families. It would be hard to prove this as the intent, but it is
certainly the effect.

11.24.050 Night parking prohibited.

No person shall stop, stand or park a vehicle at any time between the
hours of two a.m. and five a.m. upon those certain streets or portions
thereof located within a residential zone or located within three
hundred feet (300’) of a residential zone. Physicians engaged in
professional calls, persons engaged in governmental duties or
emergency activities are exempt from this provision. A “residential
zone” includes all lands located within the following zoning districts
of the city: RE, RES, R-1-S, R-1-U, R-2, R-3, R-3-A, R-3-C and R-L-U.
(Ord. 697 § 1(A), 1984).

Further background at www.menlo.org/romp

I certainly can't help you with the legal stuff, but I would point out
that the 2000 US Census reports that 57% of the housing units in Menlo
Park are owner-occupied and 43% are renter-occupied.  It's hard to see
discrimination against landlords and tenants with those figures.

< http://factfinder.census.gov/bf/_lang=en_vt_name=DEC_2000_SF1_U_DP1_geo_id=16000US0646870.html
>

You have a point. What I meant is that nobody can rent a room in their
house out because there's no room to park. Very annoying to have my
taxes pay for all that pavement and not be able to use it. My feeling
is that everyone talks about how tidy the streets are, but what is
really going on is they don't want to pay for or share facilities with
classes who by economic necessity have to crowd extra people in their
house. Keep them down by limiting cars. Seems un-American... the right
to have cars. Actually Menlo Park is famously deficient in housing
units and the State of California has been discussing fining the city
1 million dollars (1000 units short, $1000 each). The city council
just say, oh we are doing what we think our constituents want. They
also wanted a sign ordinance that got drop-kicked into orbit as soon
as a Federal judge got a whiff of it. Heck, I'm sure city council
members in the antebellum south felt that slavery was the will of
their constituents. That's why I'm looking for a legal approach to
this.

I wish my city had an ordinance like this one. Many residential
streets have functionally become one-lane alleyways because so many
people park their cars on the street.

In my view, the purpose of a street is to facilitate the efficient
flow of automobiles. Using streets as parking lots tends to impede the
movement of traffic.