This story comes out of the Arkansas Democrat Gazette. I think it raises all sorts of interesting questions about identity politics, but I don’t have the answers. So, I’ll just reproduce portions below to see what folks think.
“Rep. Richard Carroll of North Little Rock, Arkansas’ only Green Party legislator, asked to be a member of the Arkansas Black Legislative Caucus but was rejected because he’s white…. Asked about it after the meeting, Carroll said he wanted to be a member, but that caucus leaders told him that caucus bylaws require that members be black.
Caucus Chairman Rep. Nancy Duffy Blount, D-Marianna, likened the situation to a man wanting to be part of the Legislative Women’s Caucus. ‘With men, there are some things that men can understand and share and there are some things they can’t because they’re not women,’ Blount said. ‘Same thing here…’
Carroll, 52, said he wanted to be a caucus member to better represent and understand the views of his constituents. He said he could ask his wife, who is black, for her thoughts, but that she would only be one person.
‘You have to be an elected legislator and you have to be black,’ Blount said…. The latest bylaws for the caucus on file at the Bureau of Legislative Research give no race requirement for membership. It says that the membership ‘shall consist of any current member of the Arkansas General Assembly who pays an annual membership.’ But the bureau staff didn’t know whether those bylaws were current. Blount said she didn’t know either but she thought they had been changed to include a race requirement. She said she doesn’t have a copy of the bylaws but based her understanding of the membership requirements on ‘common sense’ and from what caucus vice chairman, Sen. Tracy Steele, D-North Little Rock, told her the bylaws said. Steele later said he had ‘no idea’ what the bylaws said about membership. …
Carroll wondered how the caucus ‘defines black,’ whether you needed to be a ‘certain percentage’ black. Blount said, ‘If you say you are an African-American, we don’t go back and do a historical search. We just go on whatever they say they are.’
Another caucus member, Sen. Joyce Elliott, D-Little Rock, said Carroll’s interest in the caucus is ‘commendable’ but ‘since it’s called the ‘black caucus’ he can’t be a member. It is a caucus defined as being black. All discrimination is not bad. You can discriminate about whether you are going to drink four beers or 10 beers. I would say that’s good discrimination. “‘ Elliott said excluding whites is a legitimate form of discrimination because black legislators need to join with others of ‘common cause.’
Carroll said he didn’t see it as a discrimination either. ‘It’s just that that’s their bylaws,’ he said.
It’s only a matter of time until there is a dispute over membership in the Gay Caucus. How will we tell?
Jay P. Greene's Blog 
That last question kind of answers itself, doesn’t it?
FWIW, when he was in college my brother was a member of the Society of Women Engineers. He even won a small scholarship from them, which they joked was “our diversity award for the year.”
I don’t know. Maybe they’ll require photos as proof.