I haven't heard of any hybrid cop cars but I believe there's a bunch of
hybrid Ford Escapes in use as taxis in NYC (or was it Boston? Somewhere
back east...).

Sure, I'll toss out a couple.

I was involved in the selection and procurement
a while back, so my thoughts may be old.
The major auto makers are indeed very interested
in that BIG block of sales, and will do a lot of R&D
and 'twidildy bit' production development for it (if doubt,
look at what Chev did, after Caprice folded, to make
the Tahoe a quite good pursuit vehicle!!!)
A car that proves out well for police and taxi
sales can do a big part to keep an auto assembly
factory open.

Must be very solid and durable.
Must have good maintenance and support train.
Must be quite fair size (for lotsa equipment and the
fact a ((often large)) LEO has to be comfortable
using it as his office for 8-10 hours. (see*)
Must be quite reasonably fast for the rare, but
often enough, times that is needed.
Must be decent price at fleet sale.

An example in a somewhat different area.
Alternate fuels - some switched to LNG.
Range/time on a filling became a real problem.
Not a good plan for LEO to have to take
time etc. to go to one refill spot twice in his shift.
Real bad when transport out of area, and then
not be able to refill!!!!!!

Yes, VERY good prices.
Procurement varies a lot, but what often done is the
state govt. puts out a bid.  Talking about potential of
several thousand cars at one 'whack', so they
get good sales offers.  State picks one winner in
each category.  Then all 'agencies' in state can decide
'in' or 'out' and if 'in' get at that price and add to total.

When your motor pool has 5 to 100 Crown Vics,
they have parts available and are pretty good at
quickly and efficiently working on them.
After 3-5 years, (maintenance costs rise), sell them
cheap at auction.  Still quite inexpensive per year.

And - before a storm comes in.
I am personally very frugal.  Keep my own cars
15-25 years.  That is a totally different thing.
Primarily one driver, able to mostly keep things
safe and careful.
A patrol car is a very different thing.  It is just
one of the tools we give LEOs.  24x7 operation.
What you figure for your department?? - say
one patrol car per 3/4/5/6 uniformed patrol officers?
For example I'll figure on #4, so count salary overhead,
$65,000 a year per officer, x4 = $260,000,
x3 years = $780,000.
So a $20,000 Crown Vic consumed in 3 years
is a real small part of overall cost.
Trying to force LEOs into cars that they are less
efficient in, can really cost in terms of productivity.

Every once in a while you will see some department
make news with a new Renault, Saab, Porsche etc.
Sounds fine, , but price probably 4 times what
standard was, and when need parts --eugh.
And if damaged/destroyed before end of life???

And do not forget the cost and hassell of the accesories,
radio equipment, cages etc.  Once a company has
done the work to develop a cage for sale nation wide
for a Crown Vic (and it very likely can be after 3 years
pulled out and used again!) - it reasonable cost.
For a one-off, pay through nose!

And - remember the risk assesment/liability lessons.
"The lug nut rule = in a collision, the vehicle with the
most lug nuts, generally wins."
Face it, bigger cars are safer for their occupants.
As an employer of fairly expensive employees,
covered by workman's compensation, you
would not want to put them out in bikes, mopeds,
or 1,000 lb. cars.

My thought/opinion - it (hybrid etc.) is being looked at very
closely.  Once one big agency tries - others will really watch.
If anyone gets 3 years of good records/results,
then a big switch can happen.
It probably most likely to be facilitated by a dept.
that issues a car to an LEO - take home car.
Better pride, care, and better results.

(*) bad old memories, you just stired up.
Late 1990s, Choice on the fleet purchase was
the known and good big Ford Crown Vic., and
the mid-size Chev (pre-Malibu).  I knew both
drove, worked, maintained just fine.  The selection
committee decided to get a couple of the Chevs.
along with the bulk of Crown Vics.
For a variety of reasons, many and vocal officers
decided to do what they could to avoid the Chevs.
Have you ever tried to train cats?
In many cases, it's not worth it!
Those Chevs ended up being switched to other
government administrative fleet uses.
Sometimes, Right or Wrong, is not as important
as what people will accept.