Senate Bill 1158 aims to enhance the reporting requirements for political action committees (PACs), independent expenditure committees, and recall committees regarding mass communications. The bill mandates that these committees must register if they make disbursements or incur obligations related to mass communications, which are defined as messages disseminated through various media that reference a clearly identified candidate within 60 days of an election. Additionally, all registered committees, except for referendum committees or conduits, are required to report disbursements or obligations related to mass communications in their campaign finance reports. The bill also stipulates that individuals who are not part of a committee but spend $500 or more on mass communications must report this information within 24 hours.

To implement these changes, the bill introduces new definitions for "mass communication," "mass distribution," "mass electronic communication," and "mass telephoning," and it renumbers and amends several sections of the statutes related to campaign finance. Notably, it modifies the registration requirements for PACs and independent expenditure committees, specifying that they must file registration statements within a certain timeframe after making relevant disbursements or incurring obligations. The bill aims to increase transparency in campaign financing and ensure that voters are informed about the sources and amounts of funding behind mass communications during election periods.