William Strong

“ It is an acknowledged principle that a creditor by contract has a vested right to the remedies for the recovery of the debt which existed at law when the contract was made, and that the legislature of a State cannot take them away without impairing the obligation of the contract, though it may modify them, and even substitute others, if a sufficient remedy be left, or another sufficient one be provided. ”

“ But before that day we think the relator had acquired a vested right by his judgment and his alternative writ of mandamus to have a tax levied sufficient to pay the debt due to him from the city,-a right of which he could be deprived by no subsequent action of the legislature.
We do not deny that it is competent for a legislature to repeal an act which when it was passed was a mere gratuity, if while it was in existence no vested rights have been acquired under it or in virtue of it. ”

“ It is the most the city can ask, that it be assumed the former mandate had been obeyed, and that all had been collected that could be collected under the levy. What has not been, therefore, cannot aid in satisfying the decree, and it is not averred that any part of the $170,000 can be. Notwithstanding the mandamus, it is in the power of the city to relieve herself from its binding force by paying the debt due the relator. If she can collect any thing by virtue of past levies, to the extent of the collection she will be relieved from levying additional taxes, but the debt must be paid. ”