JLARC: EV tax exemptions correlated with higher electric-vehicle counts but causal effect unclear

State legislative auditors told the House Finance Committee on Jan. 14 that eight tax preferences intended to increase alternative-fuel vehicle ownership in Washington are associated with substantial growth in electric vehicles and charging stations, but the auditors could not determine how much of that growth is attributable to the tax preferences themselves.

The Citizen Commission–mandated review, presented by JLARC staffer Pete Van Moorsil, found the set of preferences saved an estimated $98,000,000 in the current biennium and that the single largest preference — a sales-and-use tax exemption for qualifying alternative-fuel vehicle purchases — accounted for roughly $53,000,000 of that total. Van Moorsil said DOR reported “just over 40,000 vehicles took advantage of the preference,” and JLARC’s analysis shows licensed alternative-fuel vehicles in Washington rose about 230% between the preference’s start and the end of 2023.

JLARC cautioned that the measured increase includes many vehicles that did not claim the tax preference and noted other contemporaneous factors: falling EV prices, growing model availability,…