Was Criminal Probe of Ledger Star Mistreatment?

Was the DEA's investigation into the actor's death really as routine as authorities maintained?

I don't want to sound jaded, but why is there a criminal investigation into Heath Ledger's death? Thousands of people overdose every year, but I don't see a federal case being made out of their deaths. What's up with that?
—T. Freckleton

Apparently, anyone who dies of a prescription-drug overdose attracts the attention of the Drug Enforcement Administration. When Heath Ledger first died in January, the DEA insisted it was "routine," in the words of a spokesperson, for them to look into possible illegal sales of the drugs involved—in light of doctor shopping and whatnot.

I normally wouldn't buy that line, especially given the number of agents who were apparently leaping like horny salmon all over Mary-Kate Olsen and anyone else who ever breathed the same air as Ledger. It all seemed way too eager and special.

But there is one piece of information that leads me to believe that the DEA is largely telling the truth. Find out more about what I know, after the jump.

When someone dies of an overdose of a controlled or illegal substance, local law enforcement is often the first to get involved (after masseuses and Mary-Kate Olsen). But police tend to call in the DEA if they suspect that their trail leads out of their jurisdiction. In the Ledger death, police sources told the media that some of the drugs were prescribed by doctors overseas. If a case even reaches across state lines, federal investigators are much more likely to get involved.

In any case—so to speak—the DEA investigation has reportedly closed. Just like this answer.