When Mayor Street's campaign blamed a Bush administration political witch hunt for the bug found in City Hall, it guaranteed his reelection in 2006. Now, State Sen. Vincent Fumo appears poised to take a page out of that book in defending himself against federal indictment.

Fumo's legendary attorney, Dick Sprague, just held a news conference and said the charges were part of an effort by the Bush administration to drive Democrats from office.

"I suggest to you, and this doesn't just come from Dick Sprague, that the Bush administration has politicized federal investigations across the country," Sprague said. Then he offered the basis for that statement.

"Let me read to you a study of reported federal investigations of elected officials and candidates that shows that the Bush administration Justice Department pursues Democrats far more than Republicans."

Sprague then described a study that found that 79 percent of elected officials and candidates investigated by the federal government between 2001 and 2006 were Democrats, and only 18 percent were Republicans. He said Democrats made up only 50 percent of elected officeholders, and the chance of such a heavy Democratic/Republican imbalance was 1 in 10,000.

"Does that suggest something to you? Something you reporters really on the ball - instead of being spoon-fed by me or somebody else - there's a story for you. Why not make an effort to investigate that?"

Well, Mr. Sprague, I took your advice, and I am underwhelmed. I think you might wish to look more deeply at the information you have referenced, and I hope, for Fumo's sake, that you have more than this in your trial bag. Especially if you hope to back up statements you made like this:

"I suggest to you that it is the Bush Department of Justice policy to try and destroy effective Democratic leaders. And State Sen. Vince Fumo is one of those effective state Democratic leaders."

For starters, it was not easy to find the study Sprague cited. It was not in any book. Or magazine. Or peer-reviewed journal. While it was presented at something called the National Communication Association, it hasn't been published at all. The only place it's even referenced is at http://www.tpmmuckraker.com, an offbeat Web site associated with Talking Points Memo (http://www.talkingpointsmemo.com.

And there, one finds only the same summary read by Sprague at his news conference.

So I endeavored to track down one of the coauthors. I caught up with Donald C. Shields, a professor emeritus in the department of communication, University of Missouri-St. Louis. (His coauthor was John F. Cragan, professor emeritus in the department of communication at Illinois State University.) Shields told me that he had had no conversations with any of Fumo's attorneys and that I was the first in the Philadelphia media to inquire about his work. I asked him up front about his personal politics.

"I don't know what you mean by 'political bent,' " he said. "I guess I kind of believe in the Amendments to the Constitution. . . . I'm a lifelong Democrat."

That sounded fair. But any insinuation of impartiality was belied by the very first line in the abstract of the study Shields soon e-mailed to me:

"This paper examines John Ashcroft's blended religious fundamentalist and neoconservative rhetorical vision and views its impact on the political profiling of elected Democrats and moderate Republicans."

Ashcroft? Religious fundamentalism? Neoconservatives? Profiling? Throw in Hoover and Nixon, and you have the successful Street reelection platform.

I asked Shields about his methodology. How did he arrive at the conclusion that the Bush administration targets Democrats?

It seems the research done by Shields, or Cragan, or both consisted of simply hitting the Search button on Google.

Specifically, their work consisted of a tabulation of the number of times the words or phrases federal grand jury or public corruption AND elected produced a result, along with "a census search of extant press releases available at each U.S. Attorney's Office official Web site." The names of Democrats come up far more often than those of Republicans.

From that, he asks us to believe that Democrats are investigated disproportionately and presumably unfairly.

I question the conclusion because of what is not addressed, namely:

What about investigations that never get media coverage (and thus don't get on Google)? Grand jury proceedings are by definition secret, so we can never know the true extent of what's really going on.

What about the disparity of media coverage between large and small towns? The Inquirer covers Philadelphia like a glove - but local outlets may be less well-equipped to look into secret or putative investigations of their local leaders. This is an important point because investigations often are sparked off by media reports in the first place.

What about the disparity in Internet participation among newspapers? Same here. Many good investigative stories in local papers don't make it to the Web and therefore don't make it to Google.

Where is the confirmation of actual investigations? Shields and Cragan got some of their data from U.S. Attorneys' office press releases, but evidently never called those offices back to check their figures.

Why not address actual prosecutions, not just simplistic media coverage of investigations? Granted, Sprague's claim, and the study it's based on, concern investigations, but it's the cases that make it to the prosecution stage where the rubber meets the road.

Most important, what about actual convictions? (See above.)

And - dare I say? - it is theoretically possible that sometimes the conduct of members of one party may warrant more investigation than that of another?

Instead, the two retired professors whose work Fumo's attorney cited offer hyperbole such as "the political profiling of elected democrats [sic] for federal investigation of possible corruption is more than your typical Karl Rove-type, Republican campaign prank." And they claim that "the current Bush Republican Administration appears to be the first to have engaged in political profiling." (Appears to be . . . hmm . . . did they look at any other administration? Er, no.)

That was their conclusion.

Here's mine: Garbage in, garbage out.

Michael Smerconish's column appears on Thursdays in The Daily News and on Sundays in Currents. Michael can be heard from 5:30 to 9 a.m. weekdays on "The Big Talker," WPHT-AM (1210). Contact him via the Web at http://www.mastalk.com.