Try swearing at a Traffic warden see where that gets you.
If your 13 its not a problem you can swear at anyone !
Traffic wardens are great, they are trained to stand out in all weathers, be non responsive, take loads of abuse, be kicked around on a Saturday night, used as a toilet and dragged down the road under the wheels of drunk drivers and all in complete silence.
Or was that Traffic Cones
oh crap!
God you lot are on a downer. Come on take some happy pills or something. Of course there is freedom of speech, it just depends who you are slagging off and if they can see it coming.
By example:
If you call a traffic warden
"a useless pimple on the bum hole of society who should be run over repeatedly for fun until he looks like a yellow line" , its a safe bet that he might want you to stop saying any more!!
However:
If you ask him
"what does he most enjoy about his job, and how rewarding is it to be able to use all his skills within this important roll as a valued member of the community" then you might find him trying to communicate as though you are actually interested. Of course you can then just walk away totally disgusted in the middle of his answer, same message and no hassle
I know its a terrible example but I didn’t exactly have a lot to work with