My vote goes to Labradors and Golden retrievers.
Let me explain:
Of all breeds, Labradors and Golden retrievers are amongst the nicest dogs around.
And that’s the problem.
You see: owners of Labradors and Golden retrievers know this, and often (not always, because there certainly are very good exceptions !) make a very big point out of claiming “their dog would never bite a kid.”
And sadly, this is what often happens:
(1) kids get to play with nicest dog in the world;
(2) kid annoys dog (for instance, hurts it intentionally, or unintentionally touches a painful part of the dog’s body, or makes a sudden movement, or a sudden, strange noise);
(3) dog bites;
(4) (fill in the consequences).
I have had many fights with dog owners, essentially amounting to the above: being in total denial that a dog is an animal (just as humans are), and hence have their own will, and hence will react on actions they do not like.
And here is the big contradiction which is hardly understood: BECAUSE Labradors and Golden retrievers are so nice, they are exposed MUCH more to (young) kids than other dog breeds, and hence there are MUCH more biting incidents of these dogs with (young) kids.
And that should NOT be the case.