(EDIT: My mistake, sorry. It is not the ASCPA itself doing these things, just no-kill shelters in general. ASCPA itself operates very few shelters on their own, whose intake criteria aren’t readily available. They may or may not be open admission shelters.)
Gotcha. Sorry, I erroneously assumed this was just common knowledge… let me try to find some cites. I don’t know if ASPCA itself will discuss it in those terms, but I’ll try to find some other sources…
OK, so it’s more generally known as the difference between a “limited admission” and “open admission/open door” shelter: https://www.ocpomrescue.com/post/what-is-the-difference-between-a-kill-shelter-vs-no-kill-shelter. For practicality, no-kill shelters can’t accept every animal; they’d have to provide for them indefinitely, and they have limited space and funding.
Limited-admission shelters, also known as “no-kill” shelters, can be breed-specific and hold the right to turn away dogs due to poor temperament, overpopulation, inability to be adopted, or health condition. […] The dogs that are turned away from limited-admission shelters have few options left, which are dumping at an open-admission shelter, abandoning them on the streets, or taking them to be euthanized at a veterinary clinic. The limited capacity at “no kill” shelters does have somewhat of a hand in the overpopulation rates at open-admission shelters, which leads to an overwhelming number of dogs deemed as “un-adoptable” in open-admission shelters.
That isn’t in reference to ASCPA shelters and affiliates in particular, just no-kill shelters in general.
Or a NPR article: No-Kill Shelters Save Millions Of Unwanted Pets — But Not All Of Them : NPR
But she says the phrase no-kill is misleading. Unlike government-run, “open-access” shelters that take all the animals that come in, most no-kill shelters limit the number and types of dogs and cats they accept.
Or a Humane Society PDF: https://www.humaneworld.org/sites/default/files/docs/all-shelters-are-not-alike.pdf
“Limited admission” shelters usually accept only selected animals that they feel they maximize their organization’s unique skills – some focus on only highly adoptable animals that they can rehome quickly, while others might concentrate on special needs animals that their local open admission shelter doesn’t have the resources to care for.
So that’s the general concept of it. ASCPA itself isn’t explicit online about the intake criteria of its first-party shelters (at least I couldn’t find any info). I think it doesn’t like the term: FAQ | ASPCA
Because the term “no kill” has different meanings to different people, it’s not a term we typically use. The ASPCA’s number one priority is improving positive outcomes for animals. Specifically, we seek to increase the number of lives saved and decrease the number of animals entering shelters.
Anyway, ASPCA itself only has a limited number of shelters that it runs directly, and their intake criteria isn’t readily found (or they may even be open admission? not clear).
They do support no-kill coalitions: No-Kill Community Coalitions | ASPCA
But they also run a special center specifically for hard-to-adopt animals: Behavioral Rehabilitation Center for Cruelty Victims | ASPCA
So, sorry… I guess that “common knowledge” is just me reading between the lines and making my own assumptions. It is not clear to me what the acceptance criteria for ASPCA first-party shelters are. Of their partners and affiliates, each will have their own criteria. Some may be open admission. Overflow animals will go to different places depending on local availability. If an area is altogether at capacity, they may try to rehome animals elsewhere (including through ASPCA assistance).
These cites do not support the claim that ASPCA itself operates no-kill shelters (and sorry about that — I confused the national org with the local SPCA shelters that may not have any affiliation with ASPCA).