The alliance between the SNP and the Catholic Church started over 10 years ago. Plenty of articles online that go into better detail than I can. The irony is that the modern SNP socialist/liberal policies contradict many Catholic teachings and beliefs. So although it is an uneasy alliance in that respect, the benefit to both is great and there is back scratching on both sides.
In terms of this thread and issue, the most obvious example would be the SNP excluding religous and sporting institutions in their historic CSA review. The reason they gave was that it would take too long, and as a result those who did not suffer CSA from a sporting/religious institution, would be delayed in seeing an outcome. It was a shocking thing to do, and a shocking excuse, and their silence on the matter is as horrible as the actions of the perpetrators. That is why the SNP are absolutely fucking despicable, and why every right thinking person should rally against them. They are literally putting votes/independence ahead of CSA victims.