A study released Thursday by the Hollywood watchdog Center for Creative Voices in Media suggests a link between media consolidation and indecency, at least regarding the radio industry.

According to the study, based on Federal Communications Commission records, 96 percent of the FCC’s indecency fines for radio between 2000 and 2003 (97 out of 101), were assessed against four of the nation’s largest radio group owners: Clear Channel, Viacom, Entercom and Emmis.

The 11,750 stations not owned by the four major station groups (88 percent of the total number of radio stations) received four fines during the same period.

At a press briefing in Washington, Jonathan Rintels, the center’s executive director, said major group broadcasters appeared to have ended up under the FCC’s cross hairs because they replaced local programming with edgier network fare. But Mr. Rintels, who co-authored the study with Philip Napoli, an associate professor at Fordham University, said wide-ranging efforts by the federal government to crack down on indecency with beefed-up enforcement efforts and proposals to increase fines has promoted industry self-censorship that is blocking the broadcast of legitimate speech.

Mr. Rintels said the study suggests that a more effective, First Amendment-friendly cure would be to resurrect meaningful station ownership limits. “Too much speech that is not indecent is being thrown out with the dirty bathwater,” Mr. Rintels said. He said the study did not consider TV because the number of indecency fines assessed against television stations during the study period was insufficient for a meaningful analysis.