ROCK BOTTOM LINE

Madonna an innocent victim? If the role seems a tad incongruous, at least she's in good company. Along with the Rolling Stones, U2, Paul McCartney, and the Grateful Dead, Madonna has been duped by one of the country's top concert promoters, according to recent charges by the U.S. Attorney's Office. In what is expected to be an ongoing national investigation of rock promoters, the government has accused Philadelphia-based Electric Factory Concerts Inc. (EFC) of cheating more than a dozen performers out of nearly $1 million by padding bills for appearances in that city from 1987 through 1990. McCartney, for instance, was reportedly overcharged $116,397, including $17,500 for a field cover, $1,000 for plywood, $9,030 for cleaning, and $45,881 for payroll taxes. EFC, which prefers to think of the alleged extra costs as billing ''discrepancies,'' says it has already reimbursed the performers an average of $20,000 to $25,000 each. No matter what the outcome of the pending case, concert fans needn't panic. ''No one has advised us they weren't intending to book with us in the future,'' says EFC attorney Richard M. Meltzer. After all, he notes, the alleged overcharges are relatively small change for the likes of Madonna and McCartney. ''That doesn't make it correct to take money from someone,'' Meltzer says. ''But this is not a situation where the victims are exactly destitute individuals.''