The conservative think tank, The Heritage Foundation, lists a number of complaints against Chen on its blog, The Foundry.   

"Chen objected to the singing of America the Beautiful at a funeral, citing his 'feelings of ambivalence and cynicism when confronted by appeals to patriotism,'" The Foundry said in a post from last year referring to the period when Chen served as a federal magistrate in California.

The blog also noted that Chen has "endorsed the notion that judges should draw on their experiences, including 'one’s ethnic and racial background'" from the bench. 

Meanwhile Sen. Diane Feinstein, (D-Calif.), who originally recommended Chen to President Obama for the nomination, has remained a staunch supporter. 

"I hope that my colleagues will look closely at his complete record and that the Senate will confirm him soon," she said last year, according to the San Francisco Chronicle.