On Saturday — Tax Day —  protesters in cities across the country gathered to demand that President Donald Trump release his tax returns.
 
The next day, President Trump responded to the protests with a tweet that questioned their origin: "Someone should look into who paid for the small organized rallies yesterday. The election is over!"
 
It appears that the very first call for a Tax Day protest came from law professor Jennifer Taub. She tweeted the idea out back in January. Taub, who lives in Northhampton, spoke with WGBH All Things Considered host Barbara Howard about the genesis of her tweet, and what it resulted in.