IANAL, but in this scenario, I’m pretty sure you have a moral obligation to share the photos with the SDMB. 
[QUOTE=Wee Bairn]
Got it. But what about this scenario- would it be illegal?
Same photog has same topless photos. Tells Diaz “I can’t publish these because I don’t have your permission. I have no plans on ever letting anyone view them in any form. But I am short on rent money and if you would like to buy them, I am willing to sell them to you. If you chose not to buy them, I will put them in a desk drawer and never pull them out again.”?
[/QUOTE]
That sounds like a simple offer, not blackmail or extortion.
It may be illegal, Zany, but I don’t think you’ll post another comment to this thread for reasons us and only us know.

…and here’s the address to write to:
BLACKMAIL
BEHIND THE HOT WATER PIPES
THIRD WASHROOM ALONG
VICTORIA STATION’
ZZZ: in case you’re asking this because you’re writing a story in which a character tries to commit blackmail, keep in mind that being a blackmailer puts a character at enormous risk of being murdered.
[QUOTE=Campion]
Interestingly, this is an issue that’s come up before. Some people argue that settlement agreements that include a non-disclosure provision are against public policy, at least in areas like product liability or toxic tort.
[/QUOTE]
Well, if anyone ever asks you to suggest names for a spot as a federal appellate court judge, remember this moment for me.
One doesn’t need a law degree for those, do they?