These are the PARS that can be signed off, based on roles
Armory Officer: Anything that is not a test, with exception to the rifle parts test
Academic Team Commander: Everything
Marksmanship Team Commander: Rifle Parts test
Drill Team Commander: Anything drill related
PT Commander: Forming the platoon for physical training. Everything except tests
Honor Guard Commander: Anything flag/honor guard related
Platoon Commander: Forming the platoon for inspection. Everything except tests
Chiefs by PARs: Everything, with exceptions to all tests
Training Chief: Everything, as long as they keep to the binder
CO/XO/CMC: Everything
All other officers not mentioned are able to sign off on things that are not a test or does not require specific knowledge: ie Marine Corps Ranks.
All other chiefs are not able to sign off on anything, except until their actual PAR ranks.
Freshman or NS1s are unable to sign off on anything, even if they have a higher rank.