I also would like to say that we did got more of Ralph's characterization aside from "the competent cop".
It's just some of them were really subtle.
For one, he didn't care with who Fido was together with a cat. Even told Fido after the
Jata-thing that Fido should trust his teammates and friends (sure in his own Ralph-way, also yes I'm sure they're also friends with each other) so we know Ralph is loyal to his friends and really tolerant.
Aside from interactions with Kevin (who drives Ralph really nuts at times) he is most of the time super calm, I think this should count a bit for more than just "he is a competent cop", yes it helps him to be competent, but it should still count as a character trait of who is overall not just as a police dog.
Seeing how Ralph reacted to the report Sasha filled out for Kevin, he seemed to be appalled by the sheer girliness the report was oozing. Sure you could make the point he just didn't liked how an official police report was filled (and I also think that's partly the reason), but just look at his
face that's the face of someone who might say "Eeww girls have cooties" or something like that
Even if was just one time, but we know Ralph isn't above cracking some
jokes here and there, even if it's during duty.
Seeing how he tried to educate some pups during
housepets babies could be an indicator that he is friendly with puppies.
I don't think it was just for the sake of his duty, because if he wasn't I'm sure they would had send someone else. I could even imagine he did it for his own free will.
I think it's easy to say Ralph does have a solid characterization, more than just "competent" cop.
Edit:Also in many comic strips we saw him as a reasonable authority figure, so I'm sure we will get a satisfying answer for his actons.
Another question is:
What rights do pets have?
We know they don't have as many rights as humans and a big part of Keene's life was to change it, even with drastic methods.
So we know pets don't have as many rights as humans, so maybe for the housepets world what Ralph is doing is legit and not at all illegal?
I didn't saw that questioned by someone else here and if I overlooked it, I apologize.
It just feels a lot of us didn't really thought more about it aside from "it's somehow Ralph's fault."