[gigel82]

Google does not have the capability to scan local files on your device. They still have the luxury of answering "we can't" to such demands.

But Google steps on your privacy in so many other ways, it's probably not worth defending this one technicality.

[GeekyBear]

Google conducts the exact same scans on their own servers, which means the results for a single false positive must be handed over to anyone with a subpoena.

With Apple's system, no data hits their servers until multiple images match known examples of kiddie porn.

If there is a single false positive, Apple won't even know about it.

You can't provide data you never had, so Apple's system is much more private.