My girlfriend is half black and half white. While she was filling out a form recently I noticed when it came to the question of race she checked “black.” I asked her why she didn’t mark white since she is as much one as the other. She replied that in America one is considered black if the amount of black parentage is one-eighth or greater. Is or was this true? Why? Since I am a Mexican male, what will the white establishment consider our children? Not that it matters, but I’d like to know what is in store for us. –An in-love but mixed-up couple, Los Angeles

Lord knows. My advice is, if anybody asks, tell ’em the kids are Phrygian. Nobody will have any idea what you’re talking about and you’ll be able to divert the conversation to a less stupid topic.

These days there’s not much official guidance on who’s black and who’s white. The Census Bureau has adopted the sensible policy of letting you be whatever you mark down on the form. You can look like Snow White and talk like George Plimpton, but if you want to be a Fiji Islander, by God you’re a Fiji Islander as far as the census is concerned.

Things are only marginally more rigorous when it comes to stuff like affirmative action. A spokesman for the Small Business Administration says they’ll basically take your word for what race you are, although conceivably they might ask for a birth certificate or passport in the rare event there was some question.

Unofficial standards are a different story. Experts on race relations agree that up until very recently, and to some extent even today, white America held to the “one-drop” rule: if you had one drop of black blood in you–any detectable African ancestry at all–you were black. This is an extremely peculiar attitude that may well be unique in the world; even South Africa acknowledges the existence of people of mixed race.

The one-drop rule didn’t reach its full flowering until after World War I, but its roots go back to before the Civil War. Prior to 1850, mulattoes–people of mixed race–were widely recognized as being distinct from full-blooded African slaves. In fact, in some parts of the south, notably South Carolina and Louisiana, free mulattoes were a (relatively) privileged class, with money, prestige, and sometimes slaves of their own.

After 1850, however, southern whites became obsessed with the idea of racial purity and white superiority. If you had any black blood at all, you were supposed to be out back choppin’ cotton. White planters who got female slaves pregnant willingly enslaved their own children. Far from being scandalized, other southerners complained that some mulattoes remained free to pollute the gene pool.

Defeat in the Civil War only intensified these feelings. States not just in the south but throughout the union passed increasingly strict antimiscegenation laws–laws that weren’t struck down by the Supreme Court until 1967. The one-drop rule was actually enacted in only seven states (Virginia passed it in 1930); more commonly the cutoff was one-eighth black. But according to historian Joel Williamson (New People: Miscegenation and Mulattoes in the U.S.), the one-drop rule was the de facto standard throughout the country.

Williamson relates an episode from the 1920s musical Showboat in which a white boy in love with a mulatto actress is accused by a Mississippi sheriff of violating the state’s antimiscegenation law. Thinking fast, the white guy pricks his beloved’s finger with a knife, swallows a drop of the blood, and says, hey, I’m no white man, I’ve got Negro blood in me. The sheriff lets him off.

So where does that leave you? Hard to say. No question the one-drop rule still prevails for a lot of white folks. But since even racists don’t have the nerve to ask for proof of pedigree these days, what matters most is what you look like. The fact that you’re Hispanic is the perfect smoke screen. Your kids probably won’t pass for Swedish but they’ll be able to declare themselves black or Hispanic as the whim moves them. Better yet, have them say it’s nobody’s damn business.

Art accompanying story in printed newspaper (not available in this archive): illustration/Slug Signorino.