in California, unless, its a "Dog Park", all dogs are required to be on a leash at all times.
the terrier vs greyhound incident, technically took place at the boarder of the park, of what would be the sidewalk, if sidewalks were put in.

that little dog ran right up from a short distance, with little line of sight.
those are 2 big greyhounds.
i had them both on 1" wide nylon leashes.
with them pulled close at my left knee
held tight in the right hand
and the loop of the leashes around my left hand, with slack between my hands. halting the dogs.
i stomped across those dogs, to pull that terrier away from the greyhounds.
i simply stood my ground, in a Public Space.

that lady was terrified
and i thought for sure that terrier would have been torn apart

it was a bit of a scene as it was around 9am, in a neighborhood, across the street from the home of other cyclists I happen to know.

that was a case of a "happy go lucky" yippie yappy little dog that runs up to every dog to play.

I'll admit, those greyhounds are not my dogs, and I don't have more than a couple of weeks acquaintance with them. and I admit, that greyhound care is new to me. they are fast sight hounds.

that lady with the terrier was negligent in that her dog was not on a leash.
thats the law.

i was totally apologetic, and at first almost in tears, until, i realized that i was not at fault.
her dog was loose in a Public City Park, where dogs are not allowed.
I was at the boarder of the Park, on what would be the sidewalk, and the dogs were on leashes.