No, there's no emergency release switch specifically for the liftgate (rear tailgate) on a 1998 Jeep Cherokee Classic. If the liftgate mechanism fails, you'll need to access it from inside the vehicle. This usually involves removing the interior trim panel covering the liftgate latch mechanism to manually release it. The specific method varies slightly depending on whether you have a power or manual liftgate.
Consult your owner's manual for detailed instructions on accessing and releasing the liftgate from the inside, or search online for "1998 Jeep Cherokee Classic liftgate release" along with "manual" or "power" (whichever applies to your vehicle) for more information and visual guides.