Grass Snakes can actually bite. I was bitten three times during my feral childhood, when catching
Grass Snakes, lizards and
Adders (not a bright child, sadly) was one of my obsessions. It has to be said that all three bites came as I grabbed the snake as it tried to escape, and was entirely my fault for taking liberties with a good-natured reptile.
Usually,
Grass Snakes go through their defensive repertoire, which includes the 'swell-hiss-and-try-to-look-scary' routine, playing dead, and ejecting stinky muck all over you, which is nice.
These days, as a near 50 year-old and
slightly more sensible, I watch and admire, rather than hassle them in any way.