My wife and I finished the first season of the crime drama Shetland on Amazon Prime and are now onto the third season. (It seems that they skipped Season 2.)

In the first episode of Season 3, there’s a great scene where one person lays out accurately an illustration of the law of unintended consequences and the other misses the point (maybe on purpose?) and retreats to a line that makes sense only if the first person’s reasoning is right.

The main cop, Jimmy Perez, whom my wife and I generally like and who has a lot of integrity, asks a drug addict he knows about a drug that is MDMA (ecstasy) mixed with PMA. The purpose of the PMA, I gather, is to bring down the person after the high he gets with MDMA. This is relatively new on the island. Both the drug addict and Jimmy agree that it’s a toxic mix.

The drug addict explains that the reason PMA is added is that it replaces marijuana, which people had used to come down from the ecstasy high. Why replace marijuana? The addict explains that the government has done such a good job of sniffing out weed that comes to the island that the drug sellers needed to come up with a new drug that couldn’t be detected so easily. Thus PMA.

Drug Addict: It’s the law of unintended consequences.

Jimmy: It’s people trying to make a profit selling PMA.

Notice that it’s the drug addict who goes to the fundamentals. It’s true that the reason people newly make money on PMA is that there’s a new demand for it, but the reason there’s a new demand for it is that the government has squeezed out a safer drug.

The writing for this show is very good, by the way, and I don’t think it’s my imagination that Jimmy’s retort was too quick and defensive. He probably recognizes at some level, even if only for a split second, that his own law-enforcement colleagues bear some responsibility.

The picture above is of PMA.