Going rate for temp attorney work not directly involving litigation or any particularly specialty/experience is $19-34/hour. NY is typically at the higher end due to cost of living. Most temp work there is $25-34. For non-profit temp work that could potentially look good on a resume (although guess that depends in this case who is looking at the resume) $20 is reasonable, even in NYC.
I made $21 on my last project, with some minimal benefits and cash retention bonuses upon reaching specific numbers of hours on a project or with the company, in lieu of paid time off. It's a glutted market, and honest work that pays money is no insult.
Of course whether this is honest work is a matter of opinion...