Donald Trump has spent the summer slandering Mexicans as rapists and drug dealers, calling for mass expulsion of undocumented immigrants (including U.S. citizen children), and proposing to disembowel the 14th Amendment. Over the weekend he leveled an attack on DREAMers—undocumented immigrants brought to the U.S. as young children—and on Monday he released a venomous Willie Horton-style race-baiting video attacking Jeb Bush for saying that undocumented immigration can be “an act of love” by using mugshots of undocumented immigrants linked to high-profile murders.

But rather than call out Trump for his xenophobic, nativist and racist demagoguery, the other GOP White House contenders have instead settled into a shameful pattern of trying to out-Trump Trump. Instead of developing serious immigration policy solutions—something the vast majority of Americans favor—Trump’s Republican presidential rivals have lurched to the extreme right offering absurd and irresponsible ideas in an effort to outmaneuver the GOP frontrunner.

The newest ridiculous proposal came over the weekend from Chris Christie speaking at a New Hampshire Town Hall event. Christie suggested tracking noncitizen visitors like courier packages. According to the New Jersey governor it’s all quite simple, “You go online and at any moment, FedEx can tell you where that package is…Yet we let people come into this country with visas, and the minute they come in, we lose track of them.” Christie didn’t elaborate with details, so it’s not clear whether he intends to put barcodes on tourists’ backs, chips in the necks of business visitors or GPS trackers on the foreheads green card holders. I guess we’ll have to wait for his written policy proposal.

Beyond being a really dumb idea, Christie’s FedEx immigrant tracking system shows that the former federal prosecutor is also profoundly ignorant of U.S. law and policy. The Department of Homeland Security already collects biometric data—including digital images and fingerprints—from nearly every noncitizen entering the U.S. at air and sea ports. The tracking is even more intensive for other visitors including students and exchange visitors. The Student and Exchange Visitor Information System, for example, tracks and monitors foreign students after they arrive and throughout their studies in the U.S. Those who fail to show up for school are routinely arrested and detained by ICE agents who are alerted by the tracking system. The bottom line is that while it remains a work in progress, our visitor tracking has already advanced significantly since 9/11. Christie’s plan goes beyond common sense and treats people like inanimate objects.

The other problem for Christie is that tracking a person’s every move probably violates the Constitution. Earlier this year, in Torrey Dale Grady vs. North Carolina, the Supreme Court made clear that if the government puts a GPS tracker on someone—whether they’re a citizen or not—it constitutes a search protected by the 4th Amendment.

But don’t tell that to Donald Trump, Chris Christie or the other GOP presidential candidates. They’ve already proposed to eviscerate the 14th Amendment, the cornerstone of American civil rights that ensures due process and equal protection to all persons. The Republican politicians might be tempted to propose shredding the entire Constitution which, it seems, gets in the way of some of their most repugnant ideas.

Not to be outdone by Christie’s FedEx immigrant tracking system, Wisconsin governor Scott Walker—who used to be a pro-immigrant conservative before he became an anti-immigrant nativist—has made the ludicrous claim that building a border wall between the U.S. and Canada is a “legitimate” idea. He also made the unsubstantiated assertion that “Islamic extremists” are flooding the U.S. Mexico border.

Putting aside for the moment that for most of the year much of the 5,525 mile U.S. Canadian border is a frozen mass of snow and ice, there is little evidence that hordes of Canadians (or anyone else) are illegally sneaking over the border. But even if there was, why stop at building the wall at the northern border? If it’s true that about 40 percent of the undocumented immigrant population arrived in the U.S. legally on visas but overstayed, as Chris Christie claimed in New Hampshire over the weekend, then many of the undocumented immigrants probably arrived on airplanes. So why not build walls around our airports too? It might put a crimp in the take-off and landing part of U.S. and international aviation, but it’s sure to keep out illegal immigrants—along with business people, investors, entrepreneurs, artists, scientists and anyone else who adds to the fabric of our nation.

It would be unfair to leave out Louisiana Governor Bobby Jindal, who was on ABC’s “This Week” on Sunday insisting that “immigrants come here legally, learn English, adopt our values, roll up our sleeves and get to work.” When asked what he meant by “adopt our values” Jindal pointed to the example of immigrants in Europe who do not integrate into the cultures of their adopted countries. Jindal—who is a U.S. citizen because of birthright citizenship but now opposes birthright citizenship—didn’t mention that unlike the U.S. many of those countries do not have birthright citizenship and, therefore, many immigrants to Europe are not able to fully integrate into the cultures of their adopted countries.

Jindal also failed to point that American law already requires that immigrants learn to speak, read and write English to become citizens. Aspiring Americans are also tested on their knowledge of U.S. history and government. Maybe politicians like Jindal should also be required to take the citizenship test before they can run for president. The first question is “What is the supreme law of the land? The answer is “the Constitution.” The test might prove to be a more efficient way to narrow the field of presidential contenders.

Nothing that’s been proposed by Trump or those who try and mimic him will do anything to build a safe, orderly and fair immigration system. Whether it’s building a wall, mass deportation, eviscerating birthright citizenship, attacking DREAMers or tracking people like packages, none of the anti-immigrant proposals put out by Trump or the other GOP candidates will solve the problem of 11 million undocumented people living in the U.S., working hard, paying taxes and raising children. Nor will anything Trump or his GOP rivals have proposed fix the broken visa system so that it meets the needs of American business, creates American jobs, and keeps America globally competitive.

At some point Trump may have to answer for his hateful rhetoric and preposterous immigration policy proposals. But unless someone in the GOP finds the guts to forcefully stand up to his demagoguery rather than follow his lead, the Republican Party risks being branded the Party of Trump for years to come.

David Leopold practices immigration law in Cleveland. He is past president of the American Immigration Lawyers Association.