The Trump campaign and Trump's lawyer Jay Sekulow both promised to sue California when Newsom signed the law.
Trump refused to release his tax returns during his 2016 presidential bid, rejecting decades of precedent. He is already engaged in a pair of lawsuits concerning the potential release of his federal and New York state tax returns to Democrats in Congress.
The RNC lawsuit alleges that the law is “a naked political attack against the sitting President of the United States.”
And the complaint filed by Trump and his campaign claims that “Newsom and the Democrats in the California legislature who voted for it made clear that they were retaliating against President Trump for his political associations and speech.”
Both lawsuits argue that the law is unconstitutional and are seeking an injunction to block it.