Sounds good. What's the problem?
Some big unions like this thing. Large environmental groups such as Climate Solutions, Washington Conservation Voters, the Washington Environmental Council, the Environmental Defense Fund, and the Nature Conservancy like this thing. BP, who spent $13 million to kill the 2018 carbon fee initiative, and private utilities support this thing.
But the climate justice community, as represented by about 40 organizations around the state, does not support this thing. And they've got reasons.
Climate justice advocates argue Washington's cap and trade scheme won't stop air pollution at its source quick enough, and it won't lower emissions in time to meet the state's goals, mostly because big polluters use the allowances and offsets to game the market.