Can California Textbooks Criticize Slave Traders?

In California, the state laws that govern education require very specific kinds of diversity. For example, the curriculum must include "a study of the role and contributions of both men and women, Native Americans, African Americans, Mexican Americans, Asian Americans, Pacific Islanders, European Americans, lesbian, gay, bisexual, and transgender Americans, persons with disabilities, and members of other ethnic and cultural groups." And why not? They're all part of state history.

State law also forbids very specific kinds of discrimination.

For example:

No instructional materials shall be adopted by any governing board for use in the schools which, in its determination, contains: (a) Any matter reflecting adversely upon persons because of their race, color, creed, national origin, ancestry, sex, handicap, or occupation.

And why not? The U.S. Constitution arguably reflected adversely upon persons because of their race, as did a whole lot of speeches, Supreme Court decisions, and so on. So long as primary sources with antiquated assumptions about race and sex are accepted, there is no need for secondary materials that treat anyone adversely because of their race or color or national origin or sex or handicap or ... hey, wait a minute!

How did "occupation" sneak in there?

What's wrong with instructional material that reflects adversely on someone just because they were a slave trader in the 1850s or a tobacco executive in the 1980s? Is a Raymond Chandler excerpt verboten in English textbooks if the discussion questions prompt students to address how Phillip Marlowe signaled his disdain for hit men? Will chemistry books be tossed out if they disparage alchemists?

There are occupations that have been unjustly stigmatized at bygone moments in history. Perhaps this law's authors had them in mind. The law is nevertheless a good illustration of what can go wrong with efforts to mandate non-discrimination that lack intellectual clarity. Occupations are chosen, after all. With that, I'm off to check what the snake-oil-salesman lobby has been spending in Sacramento lately.