ethics madness - other gigs

i think i am now permanently confused about ethics and having jobs/gigs outside your normal employment… was there a question somewhere where a woman was on board of symphony/orchaestra and maybe did the investments. she got season tix for free and had to disclose… but didn’t have to disclose $2000 from being on board of brother-of-law’s company. might be near the question where the guy was mayor of a small town. what are the criteria? any of excessive time, investment-focus and significant money makes disclosure necessary?? thanks in advance!!!