Q. How do you cite a submission to a Royal Commission?

If you are citing an official submission that has been recieved by a Royal Commission, which is on the Commission's site, use the same pattern as an ABS document.

The author would be the person who made the submission (e.g. AMP Group or Australian Physiotherapy Association) and the "Submission to the Royal Commission into..." would be the title, with any identifying number placed in the record number position.

This is how it would look in APA 7th:

In text, you have to use the full name of the author the first time you mention them, but can then establish an acronym for subsequent citations:

The Uniting Church in Australia Synod of Victoria and Tasmania (UCA, 2020)...

Or (Uniting Church in Australian Synod of Victoria and Tasmania [UCA], 2020)...

N.B.: The entire name of the commission has to be capitalised as a name, so watch the capitalisation of the title very carefully as there may be many, many words involved in the commission's name.

If you got it from the website of the company submitting it, not from the commission's site, it might not have a number. In which case, first try to find it on the Commission's site and use that document instead (as long as they have the same conent). Otherwise treat it like any other web document. For example:

In text: 

Center for Innovative Justice (CIJ, 2020)...

Or (Center for Innovative Justice [CIJ], 2020)...