Appellant seeks reversal of a judgment of the circuit court denying his petition for certiorari filed therein to review a decision of the County Commission of Dade County denying his application for liberalization of the zoning on a parcel of land acquired by appellant under the present zoning thereof. We hold no reversible error has been shown. The matter thus ruled upon by the County Commission, as a legislative body, was a fairly debatable one. The record does not support the appellant’s contention that the county was estopped to deny his application. In absence of showing of material change in circumstances, administra*567tive res judicata of the question resulted from the prior denial by the County Commission of a substantially similar application made by appellant’s predecessor in title.

The judgment is affirmed.