Life is unavoidably unsafe
Going back to 1986, the situation at the time was a declaration of urgency by the vaccination industry that threatened to discontinue their production (and research capabilities) unless there was some kind of immunity from lawsuits. The urgency was further justified by the science at that time that vaccines are especially effective as controlling epidemics when applied to large populations of healthy people. The only ruling available to government is a permanent one that basically says from date forward to infinity vaccines are an essential part of life on earth so that any risks involved must be accepted.