Well, the Marea Weekend in the photo is used by Polizia Stradale, let's say, sort of "road police". They mainly use them for highway patrol.
In cities, "Squadra Volante" (Flying Squad - their logo being a black panther) uses the Marea sedan or, in few places, Series 3 BMWs. I am not sure but somewhere they may have Alfa 156 too. Given the logo, these cars are called "Pantere" (panthers) also because, at the beginning, they were black Alfa 1900s
In they past they only used Alfa Romeo cars, such as Giulia (in the 70s), Giulietta, 33 or 155. Just a couple of links:
http://www.poliziadistato.it/pds/chisiamo/storia/autostoriche/giulia_super_1600.htm
http://www.poliziadistato.it/pds/chisiamo/storia/autostoriche/giulietta_1800.htm
The other cars (Punto, Stilo) are not State police cars, but local police ones, so it simply is not TRUE police... State police uses some 1st serie Punto, too, but as "service" car, not for serious work ;-)
Finally, don't know about your police, but our one is definately NOT gay: it is not the car which makes the policeman...