Bava Batra 56 - False Witnesses for Chazakah
If two witnesses testified on behalf of a person that he used a property for three years, and they were found to be false witnesses, they pay the original owner everything.
Ordinarily, when two pairs of witnesses offer conflicting testimony, the result is a stalemate; the court does not know which pair to believe. However, when the second pair impugns the first pair's ability to have witnessed the event altogether, the second pair is believed, and the first witnesses are designated false (plotters). Whatever penalty they sought to impose against their victim is assessed against them.
In our case, they sought to deprive the original owner of the field by falsely testifying that the occupant has established a chazakah. Accordingly, they must pay the value of the field to the owner, who receives these punitive damages in addition to the field itself, which he retrieves from the occupant.