A debate has arisen surrounding the comments of one local GT advocate. He regularly gets up in front of groups and says that 50% of the country's prison inmates are GT.

Now, this seems like a lot of hooey to DH and me (and others I've talked to!), and while we appreciate his real point--GT kids are an at-risk population--and would never stand up and argue with him publicly, I worry that his use of what seems to be ridiculous, invented stats actually hurts his message. (Has the guy never watched "Cops"?!)

Does anyone know where to find some sort of reputable estimate about the percentage of GT prison inmates?

I Googled it, tried Ask.com, and checked SENG and DavidsonGifted.org. No luck.

There's a BBC story about the average IQ of British prisoners (around 80), which seems pretty compelling. But it isn't about American prisoners.

There's this criminology book:
http://books.google.com/books?id=u07ci3cidVsC&pg=PA173&lpg=PA173&dq=20%25+prison+IQ&source=bl&ots=uBZpbQgKHS&sig=uWNYd3k-KTKpCQ2FA1-nU_pZ3X4&hl=en&ei=NDa8SeXwOIK3twf8qrX3Cw&sa=X&oi=book_result&resnum=6&ct=result#PPA172,M1

On page 172, the book indicates a 17-point average IQ difference between habitually offending inmates and the general, non-offending population. Inmates have the lower scores. Still no numbers or percentages, though that difference makes it statistically unlikely that half of all inmates are GT, I would think.

There's also a book titled Gifted Grown Ups: The Mixed Blessings of Extraordinary Potential that apparently claims 20% of inmates are GT, though even that number seems high to me, and I wasn't persuaded that this was anything but anti-GT propoganda. I'd rather get something from a source that is at least somewhat unbiased, if not actively pro-GT. (Link here: https://gradesfixer.com/blog/the-world-factbook/ )

I could simply ask him to cite HIS source, of course. But I was hoping to be helpful and not merely difficult...

Anyone have any sources I could cite?

Thanks for any help you can offer!