The effort to implement an income tax in Seattle was a months-long effort, working through a series of town halls, committees, and the city council. The council passed an ordinance on July 10, which was signed by Mayor Ed Murray July 21.

Seattle’s progressive income tax is on individuals earning more than $250,000 and families earning more than $500,000, living in Seattle, at a rate of 2.25 percent. Proponents argue it could potentially raise up to $140 million.

RELATED: Seattle’s income tax proposal explained

Organizations such as the Seattle Transit Riders Union, Neighborhood Action Coalition, and 350 Seattle teamed up with city council members to hold a series of town halls to drum up support for the tax. They argued that it would raise money from the city’s wealthiest residents to cover federal funding cuts under President Trump; hence their slogan “Trump Proof Seattle.”

State law does not allow a progressive income tax, rather, income is legally considered property. All property must be taxed the same for all Washington residents, according to the state constitution. The City of Seattle would then take the case to the state Supreme Court. If the city succeeds, it would change the legal understanding of the state constitution and open the door for a statewide income tax, or for local jurisdictions to implement their own.

Seattle income tax timeline

• January 28: The Transit Riders Union holds a “Trump Proof Seattle by Taxing the Rich Action Meeting.”
• March 23: Councilmember Rob Johnson holds a Trump Proof Seattle town hall event.
• April 14: Councilmember Mike O’Brien holds a District 6 Trump Proof Seattle town hall event.
• April 20: Seattle’s District 2 holds a Trump Proof town hall event with Councilmember Bruce Harrell in attendance.
• May 1: Seattle council passes a resolution to support local income tax and defend it in court.
• May 4: Councilmember Lisa Herbold holds a Trump Proof Seattle town hall event.
• May 11: Lawmakers in Olympia craft legislation in an attempt to head off Seattle’s income tax plan. Representative Brandon Vick and Senator Phil Fortunato introduce companion bills to clarify the law so Seattle’s expected legal arguments won’t be successful in court.
• May 12: Councilmember Sally Bagshaw hosts a Trump Proof Seattle town hall for District 7.
• May 18: Councilmember Kshama Sawant holds a “Tax the Rich” town hall event.
• May 22: A Trump Proof Seattle town hall is held for District 5. Councilmember Deborah Juarez is invited.
• May 26: Microsoft’s Steve Ballmer warns that a Seattle income tax will hurt the local economy by de-incentivizing workers to relocate. Tech workers often move to Seattle to avoid hefty income taxes on their high pay in other cities, he argues.
• May 30: Overwhelming public support for the income tax is expressed at a council hearing on the issue.
• June 15: Councilmember Kshama Sawant calls out Steve Ballmer over his income tax statements. She argues that Ballmer’s claims are merely myths and there is no evidence to suggest that an income tax will cause any harm to the economy.
• June 16: After proposing an income tax ordinance, the City Council asks the public for their thoughts.
• July 5: Seattle income tax ordinance passes a council committee. The meeting prompts further public support, even from prominent local business owners.
• July 10: The Seattle City Council unanimously passes an income tax
• July 14: Mayor Ed Murray signs income tax ordinance.

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