% Author: Simon-Pierre Boucher — contact@spboucher.ai
% ============================================================================
\section{Conclusion}
\label{sec:concl}

Matching more than half a million residential sales to the assessment
rolls that tax them, this paper delivers the first province-wide audit of
assessment equity in Canada. The verdict is unambiguous. Quebec's
property-tax base is systematically regressive: within the same
municipality, roll and year, the assessment ratio falls by 34\% per
log-point of price in the descriptive fixed-effects estimate, and by 8\%
under the most conservative measurement-error correction available.
Ninety-five percent of municipalities fail the IAAO vertical-equity
standard, ninety-nine percent fail its uniformity standard, and the median
dwelling in the bottom local price decile pays roughly two thirds more
property tax than uniform assessment would imply, while the top decile
pays less. The inequity concentrates where mass appraisal is hardest ---
old houses, plexes, land-heavy and luxury properties, thin markets ---
doubles when triennial rolls fall behind a booming market, and disappears
almost nowhere except Montr\'eal.

These findings reframe the presumption that centralized, professionally
regulated assessment systems are immune to the pathologies documented in
the fragmented U.S. system. Quebec has uniform statutes, certified
evaluators and statutory market-vintage synchronization --- and produces
regressivity of U.S. magnitude anyway. The binding constraint is not
governance but valuation technology and revaluation frequency, which is
in fact encouraging: cycle length, pooled assessment services and
vertical audit standards are policy variables, and inexpensive ones
relative to the redistribution at stake.

The matched sale--roll architecture built here supports a research agenda
beyond this audit: linking assessment gaps to neighbourhood
socio-demographics, exploiting the discrete arrival of new rolls to study
price anchoring, and using the land--building decomposition to measure
land-value dynamics at the parcel level. We pursue these in companion
work.
