All dogs, regardless of breed, are capable of biting. All dogs have teeth capable of ripping flesh. It’s what their teeth are designed for.
Not all dog breeds have the capacity to kill within minutes.
It’s very rare for a spaniel to attack a human.
There’s a huge difference between an attack by a spaniel than an attack by a bully breed. Lots of bully breed dogs are trained, by their thug owners, to attack and fight to the death. Such owners don’t own a spaniel - for obvious reasons