A months-long Courier-Journal examination found several factors conspiring to undercut fire service in Jefferson County: * Suburban departments increasingly have moved away from using volunteers, opting instead for career firefighters who are more dependable but also more expensive, earning higher wages and greatly raising pension costs. Since 2000, suburban districts have hired 84 percent more career firefighters, increasing from 226 to 415, and reduced their volunteer numbers 29 percent, from 637 to 450. * The county's suburban districts form a patchwork quilt of coverage, where politics and protecting turf can conflict with best practices, resulting in deployment policies that sometimes prevent the closest station from responding to an emergency.