o·ver·as·sess 
(ō′vər-ə-sĕs)
(ō′vər-ə-sĕs)tr.v. o·ver·as·sessed, o·ver·as·sess·ing, o·ver·as·sess·es
1. To assess (a property) as being worth more than its actual value, leading to the imposition of an overly high tax based on the valuation.
2. To collect a tax higher than that justified by law from (someone).
o′ver·as·sessment n.