There are T-shirts for sale now that say cocaine is "The Real Thing." But in Fairfax County, you never know.

Commonwealth's Attorney Robert F. Horan Jr., who has custody of about $25,000 worth of cocaine, says that because of the Fairfax County Circuit Court decision Thursday no one knows for sure if the cocaine in his custody is, in fact, the real thing.

"This is the wildest issue I could dream up," Horan said yesterday.

There are two kinds of cocaine: one is derived from coca leaves and is illegal under Virginia and federal law; the other, synthetic cocaine, is simply not mentioned in Virginia or federal laws. Synthetic cocaine is virtually impossible to obtain in the United States, according to drug enforcement officials.

Circuit Court Judge Barnard F. Jennings ruled Thursday that the prosecution failed to prove the cocaine allegedly sold to an undercover agent by Richard Gobeille, 28, of Annandale, was the illegal kind. The chemical tests necessary to distinguish synthetic from organic cocaine had not been performed before the trial. However, Horan said the tests will be conducted soon.

In the meantime, Horan is stuck with two plastic bags of white powder that may or may not be a controlled substance. "The law permits us to destroy a controlled substance," Horan said. "But what are you supposed to do with something that is not a controlled substance?"

Horan asked another question yesterday in the wake of Jennings' decision to dismiss charges against Gobeille, who faced three counts of cocaine distribution, each carrying 40-year maximum sentences. "What if the defendant comes in (to the prosecutor's office) and says, 'Give me back my non-controlled substance'?"

Jonathan Shapiro, one of Gobeille's defense attorneys, said Horan need not worry about that. "I don't think my client has any intention of going near that stuff," Shapiro said.