When James Laski finished serving his 11-month prison stint on corruption charges in 2008, he knew his political career was over. But the former Chicago city clerk had every reason to believe his rap sheet was no barrier to another coveted, high-profile job: Chicago radio broadcaster.

For Chicago politicians, it seems, breaking the law can serve as prelude to a seat before the microphone.

When Mr. Laski begins his new weeknight show on WGN-AM on April 12, he will become the third convicted or indicted Illinois politician with a regular presence on local radio. Cliff Kelley, convicted in 1987 of accepting bribes while alderman of the 20th Ward, is an integral part of WVON-AM, commanding four hours every weekday afternoon on that African-American-oriented station. Rod R. Blagojevich, the impeached governor whose federal corruption trial is set for June, has a two-hour Sunday show on WLS-AM.

Chicago is not the only place where disgraced politicians have reinvented themselves over the airwaves. But the city is brimming with tainted politicians turned professional talkers.