In 1868, in the aftermath of the Civil War, the United States adopted the 14th Amendment to the Constitution.  Section 1 of that Amendment contains what is known as the Equal Protection Clause:  ". . . [N]or shall any state . . . deny to any person within its jurisdiction the equal protection of the laws."  That's the whole thing.  What could be simpler?

And now last week we have a judge in California in a case called Vergara invalidating the entire California system for  job security and tenure for teachers based on this Equal Protection Clause.  According to this report from Edvard Pettersson of Bloomberg, "Judge Rolf Treu in his tentative ruling found that low-income and minority students are disproportionately stuck with “grossly” ineffective teachers, leading him to conclude the challenged laws violate the students’ fundamental right to equality of education." 

Needless to say, the teachers unions and so-called "public education advocates" are up in arms.  Here is a round-up of their reaction from Sarah Lazare at Common Dreams.  From Dean Vogel, president of the California Teachers Association:

 This lawsuit has nothing to do with what’s best for kids, but was manufactured by a Silicon Valley millionaire and a corporate PR firm to undermine the teaching profession and push their agenda on our schools.

And this from Chicago:

 [C]ommunications director for the Chicago Teachers Union Stephanie Gadlin called the ruling "ludicrous" and "hypocritical."

The generally sensible Megan McArdle of Bloomberg View nominates the court's decision for a "Dunce Cap":  

[T]his does not seem like a very good ruling to me. Political partisans on both sides tend to treat "unconstitutional" as a synonym for "things I think oughtn't to be allowed." This is not correct, and moreover, it is profoundly destructive. The courts don't owe reverent deference to the legislature, but I do think that we should restrict the meaning of the word "unconstitutional" to, well, things the constitution doesn't allow, rather than expanding it to things the constitution shouldn't allow. Every time we use the latter definition, we travel further down the road toward rule by unelected boards of elderly lawyers.

Excellent point, Megan.  But isn't equating "unconstitutional" with "things I think oughtn't to be allowed" what the Equal Protection Clause has been about for a long time?  For decades the Equal Protection Clause has been the all-purpose mechanism for the Left to implement the items of its agenda that could not get through a legislature.  Well, you may achieve some result you like today, but now you have conceded great power to what Megan calls "unelected boards of elderly lawyers," and some day they are going to make some very major decisions that you don't like.  And then, what are you going to do about it?

The problem with the Equal Protection Clause has always been that of course every law treats some people differently from others; indeed, generally that's the whole idea.  For example, criminal laws impose crushing burdens on criminals, and few burdens at all on the law-abiding.  Could that really be unconstitutional?  If not, what is the principled distinction between that and all the other instances where equal protection challenges have been upheld?

McArdle prefaces her argument with the admission that "I Am Not a Lawyer," seemingly conceding that lawyers must have some insights into the proper boundaries of the equal protection elixir.  Well, I am a lawyer, and if there are any such boundaries I've never figured them out.  You can know as much about this as pretty much any lawyer by reading the next couple of paragraphs.

After the enactment of the 14th Amendment, the southern states proceeded to implement the system of overt racial segregation known as "Jim Crow."  In 1896 a case called Plessy v. Ferguson reached the Supreme Court, challenging a Louisiana statute that mandated segregated accommodations for blacks and whites on railroads.  The Supreme Court upheld the statute and, more generally, the concept of so-called "separate but equal facilities."  And there the matter stood until the famous 1954 Supreme Court decision in Brown v. Board of Education, which reversed Plessy and held that segregated public schools were inherently unequal and therefore violated the Equal Protection Clause.  Brown brought about a revolution in public education, with federal judges basically taking over and running hundreds of local school districts.  Essentially nobody today would disagree with Brown as it applies to de jure racial segregation.  But the problem with Brown is that it set no boundaries for the invocation of the Equal Protection Clause.

And thus we have six succeeding decades in which the courts have found one new area after another for applying the Equal Protection Clause to invalidate large swaths of state laws and even state constitutions.  As just a small partial list, consider:

•  Baker v. Carr (1962), where the Supreme Court decided that districting of state legislatures implicated the Equal Protection Clause, and (together with subsequent cases) required all states to draw districts in accordance with the principle of "one man, one vote."  (If applied to the federal government, this principle would invalidate the Senate.)  Since 1962 the federal courts have micro-managed many state legislative districting decisions.
• Serrano v. Priest (1971), where the California Supreme Court invalidated the state school finance system, which had been largely derived from local property taxes, again based on the Equal Protection Clause.  The Serrano decision was then followed by the courts of numerous other states, who forced on state legislatures new financing systems that had not previously gained democratic support.
• Plyler v. Doe (1982), where the Supreme Court struck down as a violation of equal protection a Texas statute that denied funding to local school districts for the education of children who were not "legally admitted" into the United States.
• The fight for same-sex marriage has proceeded largely under the banner of the Equal Protection Clause (although on this one, the Due Process Clause has also gotten into the act; for example, the Supreme Court found the basis to strike down DOMA in the 5th Amendment's Due Process Clause, since the Equal Protection Clause of the 14th Amendment only applies to the states).  Numerous courts, federal and state, have used the Equal Protection Clause to strike down one or another statute or referendum that attempted to restrict marriage to a man and a woman.  (Note that New York has about the most honorable record of any state on enactment of same sex marriage:  the Court of Appeals in 2006 declined to order it as a matter of the constitution, and thereupon the state legislature enacted a legalizing statute in 2011).

At this point the Equal Protection genie has been out of the bottle for a long time.  Judge Treu's decision may seem a stretch at first blush, but is it really much more of a stretch than Serrano, which is indeed the main authority on which it relies?  Seems to me that those who have never to date spoken out about overreaching equal protection jurisprudence but now argue that the Vergara decision is wrong have a burden to articulate some kind of a principled boundary on where the Equal Protection Clause ends.  And that boundary had better not be too obviously reverse-engineered to preserve just the decisions you like.