Teachers in the warehouse

Here is an interesting phenomena.   Let's say there is an allegation about a teacher that involves an offense that could lead to dismissal.  The most obvious would be an accusation of child abuse.  of course, the individual deserves due process before such action can or should be taken.  But how long does this investigation and due process take and what happens to the teacher during that process.
If the teacher works for a school system that is represented by a union, that process could take over a YEAR!   And during that time, the accused teacher is paid full salary each and every day and receives all benefits.   During the day the teacher reports to a kind of "holding tank".   In some school systems the "holding tank" is a book warehouse.   Here the pariahs read, play cards, use their smart phones and chat with each other.  All on the taxpayers' dime.   There are also supervisors watching because sleeping is not allowed, so if a person should doze off during the so-called workday, the supervisor wakes that person up.
Back in the teacher's class for which the teacher is being paid, a substitute is holding forth.   A permanent teacher cannot be hired for this spot because technically it is not an open spot.  So let's add this all up:  alleged wrongdoers salary $67,000 (the average in a metro school system), alleged wrongdoers benefits $9,300 (calculated at 14% of gross, which is probably low), the substitute's salary $45,000, and substitute reduced benefits because the person is a sub $4,900 (calculated at 11%).  That is over $126,000 without introducing the overhead costs of the warehouse itself.   AND the kids, oh right, there are students in this equation.  They are being taught by a substitute who may or may not be trained in the field.
Why do we do this crazy thing?   Well because it is written into the union contract to protect the teacher from false accusations.  I know of no other job or profession in which a person is paid full salary and benefits during a due process procedure.   And if the person is found to be guilty, there is no compensation to the school system, nor the taxpayers and certainly not to the children for all the money spent during the process and the instruction lost.
How about speeding up the process to 90 days and not pay the teacher during the process.  This procedure might speed up the motivation of the teacher to resolve the matter.  If the teacher is found innocent, the teacher could get back pay.  If the teacher is found guilty at least the taxpayers have not funded a perpetrator and the students are deprived of a qualified teacher for a finite amount of time.  Teachers' unions function to protect the teachers, good and bad.  But why do we have to be complacent in that function.