Former Bush administration Attorney General Alberto Gonzales penned an op ed in the Washington Post backstopping Donald Trump's claims that the judge presiding over the lawsuit brought by former Trump University students is biased.

But instead of trashing Judge Gonzalo Curiel’s Mexican heritage, Gonzales suggests a far more effective attack; his ties to the Democratic party and specifically, Hillary Clinton.

Certainly, Curiel’s Mexican heritage alone would not be enough to raise a question of bias (for all we know, the judge supports Trump’s pledge to better secure our borders and enforce the rule of law). As someone whose own ancestors came to the United States from Mexico, I know ethnicity alone cannot pose a conflict of interest.

But there may be other factors to consider in determining whether Trump’s concerns about getting an impartial trial are reasonable. Curiel is, reportedly, a member of a group called La Raza Lawyers of San Diego. Trump’s aides, meanwhile, have indicated that they believe Curiel is a member of the National Council of La Raza, a vocal advocacy organization that has vigorously condemned Trump and his views on immigration. The two groups are unaffiliated, and Curiel is not a member of NCLR. But Trump may be concerned that the lawyers’ association or its members represent or support the other advocacy organization. Coupled with that question is the fact that in 2014, when he certified the class-action lawsuit against Trump, Curiel appointed the Robbins Geller law firm to represent plaintiffs. Robbins Geller has paid $675,000 in speaking fees since 2009 to Trump’s likely opponent, Hillary Clinton, and to her husband, former president Bill Clinton. Curiel appointed the firm in the case before Trump entered the presidential race, but again, it might not be unreasonable for a defendant in Trump’s position to wonder who Curiel favors in the presidential election. These circumstances, while not necessarily conclusive, at least raise a legitimate question to be considered. Regardless of the way Trump has gone about raising his concerns over whether he’s getting a fair trial, none of us should dismiss those concerns out of hand without carefully examining how a defendant in his position might perceive them — and we certainly should not dismiss them for partisan political reasons.

I think it's futile to suggest that Curiel's Mexican heritage is a reason for the judge's treatment of Trump. First of all, it's impossible to prove. His parents arrived in America almost 100 years ago and Curiel was born, raised, and educated in America. Secondly, there is no hint in Curiel's previous opinions of any kind of political bias. It seems Trump has made a completely scurrilous charge with no basis in fact in an attempt to distract voters from the fraudulent scheme perpetrated by Trump University on students.

Gonzalez offers a far more profitable line of attack, citing irrefutable facts and raising legitimate questions about the fairness of the judge. But Trump seems determined to get a rise out the bigots who support him rather than actually try and defend himself from a possibly biased judge.