Swearing of Affidavits During COVID-19 Restrictions in Tasmania:

Supreme Court
All 3 Supreme Court registries are open, and JPs are available there to witness sworn documents.

Federal Court
Currently closed to the public.

Service Tasmania
Offerings temporarily unavailable.

Find a local JP:
The Tasmanian Government has also produced a facts sheet relating to services provided by Justices of the Peace during the coronavirus pandemic.