Sixteen states, including New York, have joined a lawsuit filed by Xavier Becerra, attorney general of California, challenging the Trump administration’s move to acquire funds from government agencies to build a wall along the Mexican border.

This is the first major challenge to Trump’s determination to gain the funds by whatever means, including an end run around a Congress which had rejected his demand for more than $5 billion to build the wall.

The lawsuit was filed on Presidents Day, when “we should be celebrating what our presidents have done for this country, that we’re actually suing the president,” Becerra told the press during an interview Feb. 18. The president, he said, “must abide by the law. No one is above the law in this country.”

In invoking a so-called emergency in order to get the funds needed to build the extensive wall, Trump apparently feels the $1.375 billion approved by Congress last week is not enough. He predicted that he would be sued but plowed ahead anyway. “We’re going to confront the national security crisis on our southern border,” he announced last week. “And we’re going to do it one way or the other.”

By pushing ahead with his agenda, Trump believes in the long run that lawsuits will probably end up in the Supreme Court where he can rely on a conservative-leaning court to rule in his favor.

Thus far, along with New York and California, Colorado, Connecticut, Delaware, Hawaii, Illinois, Maine, Maryland, Michigan, Minnesota, Nevada, New Jersey, New Mexico, Oregon and Virginia have signed onto the lawsuit.

“Declaring a National Emergency when one does not exist is immoral and illegal,” New York Attorney General Letitia James said in a statement. “Diverting necessary funds from real emergencies, crime-fighting activities and military construction projects usurps congressional power and will hurt Americans across the country. We will not stand for this abuse of power and will fight using every tool at our disposal.”

Key to the lawsuit is Trump’s belief that an emergency exists, which runs counter to what the plaintiffs believe. “Unlawful southern border entries are at their lowest point in 20 years, immigrants are less likely than native-born citizens to commit crimes, and illegal drugs are more likely to come through official ports of entry,” James added. “There is no credible evidence to suggest that a border wall would decrease crime rates.”