By Ray Stern

Maricopa County Attorney Andrew Thomas is too high.

Too high, that is, when it comes to the hysterical statistic quoted in his new public service announcement about drop houses.

Like much of the government propaganda about drugs, Thomas' PSA uses a questionable stat to grab our attention: "About 90 percent of illegal drugs come from south of the border."

Nobody doubts that plenty of illegal drugs are funneled through Mexico on the way to the United States. But Ramona Sanchez, spokeswoman for the local office of the DEA, says it's more like 60 percent or so.

The PSA, launched last week following a press conference with Sheriff Joe Arpaio, is mainly about Thomas' favorite subject, illegal immigration. The PSA begins with the vague, disputable opinion that "illegal immigration is fueling Arizona's violent crime and drug problem." Viewers are reminded of the violence illegal border crossers sometimes suffer at the hands of their smugglers, and then are asked to call Arpaio's immigration snitch line to report possible drop houses.

In fact, most drop houses are busted only after citizens call police to report them. Thomas and Arpaio are probably hoping the ad funnels more of the calls to the Sheriff's Office, which can then boast about arresting higher numbers of Mexicans.

Linking illegal drugs to illegal immigrants, in general, seems nothing but a fear tactic. The idea put forth in the ad is that if you support Thomas and Arpaio's approach of busting run-of-the-mill illegal immigrants, you'll make a dent in the illegal drug trade. But that's unprovable nonsense.

Even if 90 percent of drugs really came from south of the border, there's no reason to think tougher immigration enforcement would dry up the supply of drugs in this country. Drug cartels often react to enforcement changes by changing their transport routes, and would do so again if traffic from Mexico was slowed. A 2007 report from the Government Accountability Office states that although 90 percent of the cocaine in the U.S. comes from south of the border, that's a fairly recent change: It was only 66 percent in 2000.

Sanchez, of the DEA, says other drugs, like marijuana or heroin (not to mention illegal prescription drugs), come through Mexico less often than cocaine. "The percentage is going to be different for each drug," she says.

The idea that "90 percent of illegal drugs come from south of the border," as Thomas' ad says, "would seem impossible," Sanchez says.

So where did Thomas get his "90 percent" statistic? Well, his own Web site states that it came from a conservative writer's opinion article.

The public paid $800,000 to produce and air the ad, according to Thomas' office. Guess not much of that was spent on quality research.

The writer, Robert Caldwell, published the figure in the article. But it's unknown where he obtained the figure — he's a retired editor from the San Diego Union-Tribune and could not be reached Thursday.

A bit of Internet research showed that members of Congress saw that figure in the text of the Merida Initiative, a law signed by President Bush in June that gives money to Mexico to fight illegal drugs. The law cites the GAO as the source, but the data seems to have been skewed, as if it were part of a game of telephone. As noted above, the latest GAO report on the subject merely talks about the 90 percent of cocaine coming from Mexico. A 2007 State Department report on illegal drugs also implies the 90 percent figure should be applied only to cocaine.

Thomas may not care that his ad contains a garbage statistic. After all, the ad effectively makes illegal immigrants look like scumbags.

And that could be the point: Maybe Thomas sees the ad as a way to help justify to the public his harsh, expensive immigration-enforcement programs.