The seating arrangements for a debate at University College London Saturday have led prominent atheist Richard Dawkins to accuse the event’s Muslim organizers of “sexual apartheid,” but the group is challenging his version of events.

The debate, “Islam or Atheism: Which Makes More Sense?,” pitted physicist Lawrence Krauss against Islamic lecturer Hamza Andreas Tzor. Seating was in three sections — one reserved for men, one reserved for women, and one that was mixed. (More on that “mixed” section in a moment.)

Krauss, who had heard rumors about separate seating prior to the event, apparently asked for, and was granted, permission to announce that anyone could sit where they liked. But according to a colleague of Krauss’s, three men who then moved to the women’s section were soon ejected from the room.

At that point Krauss declared that he would not participate unless open seating was permitted — an iPhone video posted on Facebook shows him saying, “I’m not going to be an auditorium that’s segregated. I’m sorry. I’m not. Either you quit the segregation or I’m out of here.”

Krauss left the auditorium at that point, but returned after the three men were allowed to take seats in the section they had been ejected from. The debate then went on as scheduled.

In a blogpost earlier today, Dawkins claimed that the room was divided into sections for men, women, and “couples,” echoing language used by Krauss associate Dana Sondergaard, source of the iPhone video. Organizers, however, say that the sections for men and for women were for the use of those “choosing to adhere to orthodox Islamic principles,” and that “those who wanted to sit together, male or female,” were welcome to sit in the mixed seating area.

The debate’s organizers tell the Guardian that University College approved the seating arrangements in advance, but the Guardian reports that UCL has opened an investigation into the event.

Separate seating for those who prefer single-gender sections is not unheard of at Muslim student events in the United States, but if the organizers’ claims are accurate and mixed-gender seating was made available for anyone who wanted it, Dawkins’ rhetoric of “apartheid South Africa” and “Alabama in 1955″  seems inaccurate and ahistorical. There weren’t mixed sections for those who wanted interracial seating at public events in those societies — segregation was compulsory and enforced by law.

I’ll be following this story as it develops, and reporting what I learn.

Update | Krauss tweets that debate organizers told him today that their intent was for separation of audience into three sections to be entirely voluntary, and that the move to eject the three men sitting in the women’s section was a result of flawed “communication to and from staff.” He reiterates that he was told there was to be no separation whatsoever, voluntary or not.

This clarifies my own position a bit. I don’t have any problem at all with a group saying “we have attendees at this event who’d be more comfortable for religious reasons sitting in single-gender sections, and we’d ask that everyone respect that.” I have a big problem with only providing gender-segregated seating at a public event. As for the middle case, in which organizers ask (or tell) men to leave a women’s-only section? That’s one that I’d need to chew on more, and to consider the specific circumstances of.

Second Update | An apparent eyewitness account provided to the UCL administration by (Google suggests) London School of Economics grad student Chris Moos suggests that the provisions for gender-neutral seating were far less robust than the organizers have claimed.

Moos, as quoted on this blog, says organizers forced men and women to enter the lecture hall through separate doors. As for mixed-gender seating,

“There were no signs for a mixed seating area, and attendees were guided by the guards to either the “female” or “male” area. Only attendees who insisted not to be separated were guided towards a “mixed” area, which only comprised two rows.”

Moos also claims that only men and “couples” were allowed to enter through the men’s door.

Another post on the same blog quotes Fiona McClement, UCL’s “equalities and diversities adviser,” as saying priot to the event that the college “will not permit enforced gender segregated seating. All attendees are free to sit wherever they feel comfortable.” That blogpost also alleges that “male attendees were refused entry via the women’s door to the lecture theatre.”

So yeah. It sounds like this was quite a bit worse than I’d expected based on Dawkins’ original post. At the same time, however, there’s this:

“It’s insulting to be told that because I’m a man I can’t sit near women in the audience. I’m not in the habit of forcing my presence where it’s unwanted, but the event’s organisers have no business policing social matters of this kind. … In this case the segregation was non-voluntary. But voluntary or not, segregation is wrong.”

A couple of things.

First, voluntary “segregation” isn’t segregation. It’s separation. And it’s not wrong. If I want to sit with my friends at lunch, that’s not segregation. When the Black Student Union holds meetings and only black people show up, that’s not segregation. If women having a support group about sexual assault ask a guy who wanders in to leave, that’s not segregation. So no, voluntary “segregation” isn’t segregation, and it’s not (presumptively) wrong.

Second, if women would prefer, for religious reasons, to sit with other women, it’s not “insulting” anyone else if they do so, and it is “forcing your presence where it’s unwanted” to sit next to them.

This is complicated stuff. Reductive first principles don’t get us very far, and appeals to common sense get us even less far.

Again, though, having said that? It sounds likely that what went on at this event was pretty messed up.

Third Update | UCL has released a statement. They say that “enforced segregation” is prohibited on campus, and that they told the debate’s organizers that “the event would be cancelled if there were any attempt to enforce such segregation.” The statement continues:

“It now appears that, despite our clear instructions, attempts were made to enforce segregation at the meeting. We are still investigating what actually happened at the meeting but, given IERA’s original intentions for a segregated audience we have concluded that their interests are contrary to UCL’s ethos and that we should not allow any further events involving them to take place on UCL premises.”