They have complained about the treatment of employees at the company's Carl's Jr. and Hardee's chains, as well as Puzder's opposition to increasing the federal minimum wage to $15 an hour, among other views.
On top of that, Puzder admitted this week that he had employed a housekeeper for years who was in the U.S. illegally.
"On policy and practice, Andrew Puzder has proven himself to be an enemy, not a champion, of workers' rights," Senate Minority Leader
"They ought to withdraw Puzder's [nomination] before he further embarrasses this administration and further exposes the hypocrisy of President Trump saying one thing to the workers of America and then doing another," Schumer said.
"Not only is Andrew Puzder uniquely unqualified, but his decision to pick and choose what laws he himself follows is disqualifying," Murray told reporters.
A spokesman for Puzder said the housekeeper was employed about five years ago but that Puzder paid the back taxes only after Trump announced his intention to nominate him in early December.
The focus on Puzder comes after Democrats have been unable to derail other cabinet nominees they've opposed. Murray said Democrats are focusing on him now because his confirmation hearing is set for Feb. 16.
The hearing had been delayed four times as senators awaited Puzder's ethics and financial disclosure forms.
The Senate Health, Education, Labor and Pensions Committee now has received the paperwork, in which Puzder pledged to divest his multimillion-dollar stake in CKE Restaurants and sell a wide array of other investments.
Puzder also promised not to participate in any matters as Labor secretary involving CKE Restaurants unless he received a waiver or authorization in conjunction with federal law.
The forms, filed with the Office of Government Ethics, were obtained by The Times on Wednesday.
The 33-page disclosure report showed Puzder had $35 million to $119 million in assets, which are required to be reported only within broad ranges.
His stake in CKE Restaurants is worth between $11 million and $55 million. Puzder listed liabilities of nearly $4 million to $12 million, mostly mortgages on two personal residences.
Puzder said he received $3.4 million in salary and bonus from CKE Restaurants last year. He said he would resign as chief executive "upon confirmation" and would not receive any severance or deferred compensation.
He said he would keep the estimated bonus of $1 million to $5 million that he is owed this year and reimbursement of $250,000 to $500,000 for his move to Tennessee, where CKE's corporate headquarters is relocating this year, if he receives the money before he takes office.
If confirmed, Puzder said he would sell his holdings in 213 companies and other investments within 90 days. Within 120 days, he said he would sell holdings in 13 investment funds.
Democrats have been critical of labor law violations at CKE Restaurants, and fast-food workers have staged protests against Puzder's nomination in Los Angeles and elsewhere. Workers in the Fight for $15 movement are planning rallies against Puzder Monday at CKE's Anaheim offices and in two dozen other cities.
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