Last week, New York Mayor Michael Bloomberg put the world on notice that when an open borders enthusiast talks tough on enforcement, he’s probably faking it.

Bloomberg testified before the Senate Judiciary Committee’s hearings on immigration reform in Philadelphia, convened to counter the House’s simultaneous hearings on the costs and risks of illegal immigration. The mayor offered an eloquent defense of open borders. The flow of people into the United States is a force of nature, beyond mortal control, he said. We can no more stop the influx than a beachgoer can stop the tides. The decision about whether to enter the country and under what conditions is entirely the immigrant’s, not the American people’s.

But not to worry, Bloomberg reassured his audience. Immigration is at all times and in all forms an unmitigated boon. Illiterate, literate, skilled, unskilled—all immigrants are necessary. Without our current levels of immigration, Bloomberg said, the New York and national economies would “collapse” (apparently New York business deals rest precariously on free pizza delivery and low-cost restaurant dish-washing).

In fact, we risk collapse for lack of immigrants, Bloomberg warned. High-skill industries like science and medicine are growing faster in other countries, he claimed. The solution: more immigrants—manual laborers as well as engineers. But no country has a higher rate or absolute number of immigrants than the U.S. If other countries are producing more skilled graduates, maybe it is because their school systems aren’t saddled with an ever-growing pool of foreign students from cultures that do not highly value academic achievement and their schools aren’t dragged by ethnic politics into enforced academic mediocrity.

Predictably, Bloomberg called for amnesty for the 12 million illegals already here. Like all such advocates, he held out mass deportations as the only alternative—a straw man “solution” that no serious immigration reformer has proposed.

Yet Bloomberg also tried to sound like an immigration cop. He decried the federal government’s failure to penalize employers who hire illegal aliens. He mocked the 1986 immigration reform law that prohibited employers from verifying a worker’s legal status. He called for a biometric social security card that would defeat counterfeiting. And he wanly conceded that perhaps a little bit of fencing on the border might be necessary, though he would prefer a “virtual wall.”

So is a commitment to immigration enforcement compatible with the belief that the U.S. has a duty to take all non-terrorist comers, regardless of whether they enter in the trunk of a car or through customs? Nope. The ending of Bloomberg’s testimony thoroughly undermined his gestures toward the rule of law, making clear that the instincts that lead people to support amnesty and an unrestricted right of entry will defeat enforcement in the blink of an eye.

In those final remarks, Bloomberg blasted a House proposal to penalize cities and counties that have “sanctuary laws.” These ubiquitous laws prohibit local government employees from notifying federal immigration authorities about the presence of illegal aliens. Sanctuary mandates create vast law-free zones where illegal immigrants know that they face virtually no risk of apprehension; the zones have notoriously protected criminals as well as itinerant roofers.

In 1996, Congress responded by prohibiting local governments from restricting the speech of their workers in this way. To no avail. Virtually every sanctuary city proceeded to ignore this new federal law as well as the preexisting immigration laws. New York Mayor Rudolph Giuliani took his defiance to federal court. He lost his suit against the 1996 law, but—on September 10, 2001—declared his intention to continue violating it anyway.

Mayor Mike Bloomberg has gone even further in backing the sanctuary policy. In 2003, the city faced a massive public relations fiasco following the rape of a Queens mother by a group of illegal Mexicans. New York police had arrested several of the Mexicans previously for other crimes, but reported none of them to the immigration agency. Congress hauled in the city’s criminal justice coordinator to testify about the city’s sanctuary law, after which Mayor Bloomberg—amazingly—strengthened the policy. And last week he declared his defiance of the Congressional will yet again. If Congress goes forward with its proposal to cut homeland security funds to localities with sanctuary rules, he told the Senate Judiciary Committee, it would have “one heck of a battle” on its hands.

Bloomberg’s discussion of New York’s sanctuary law, like the law itself, was a clever piece of evasion. Trying to sound reasonable, the mayor told the hearing that “New York City cooperates fully with the Federal government when an illegal immigrant commits a criminal act.” But the crucial issue is whether the New York Police Department will report an illegal crime suspect to Immigration and Customs Enforcement, or whether it will merely “cooperate” with ICE when the federal agency is already seeking an illegal suspect. When the NYPD stops the next potential illegal rapist on a robbery charge, in other words, will it tell ICE to come and get him?

Bloomberg’s updated sanctuary policy, Executive Order No. 41, is as misleading on this question as was his testimony. The order declares that law enforcement officers shall “cooperate with federal authorities in investigating and apprehending aliens suspected of criminal activity” but leaves ambiguous the question of the NYPD’s affirmative duty to report. City officers may report an illegal alien suspected of non-immigration-related illegal activity but have no obligation to do so.

So how does the NYPD interpret its authority? Asked what the threshold was for reporting an illegal alien suspect to ICE, the NYPD press office simply referred to Executive Order No. 41—itself silent on the matter. Nor could the department say how many suspects it has reported to ICE over the past year and whether they represented all of the undocumented suspects who have come to the force’s attention. The department simply does not keep statistics on such matters. Needless to say, this ignorance about a crime problem and about the official response to it represents a remarkable lacuna of record-keeping for an agency that lives and dies by the numbers.

Maybe ICE would know about how many illegal alien criminals the NYPD has reported to it? If so, it isn’t saying. Department of Homeland Security spokesman Mark Raimondi replied diplomatically when asked about the NYPD’s illegal alien reporting: “We have a strong working relationship with the NYPD; we work closely with the department and solve a lot of crimes together.” Yes, but there is this little matter of Executive Order 41. “The order does at times prevent the NYPD from sharing information that we’d like to have,” admitted Raimondi cautiously.

It’s hard to blame the NYPD for what looks likely to be passivity regarding the reporting of illegal alien criminals. The message from the mayor’s office and from New York political elites runs in exactly the opposite direction, and without a clear affirmative mandate regarding illegal reporting, the safe policy is to do nothing. Executive Order No. 41 lays out the remarkable proposition that one’s status as an illegal alien is “confidential information” of the same order as one’s sexual orientation, status as a victim of sexual assault, or tax records. Mayor Bloomberg really does believe that illegal entry is an uncontrollable force of nature like “the tide,” as he puts it—people who come here illegally are no more responsible for their movements across the border than pieces of plankton. Given the protections that Executive Order No. 41 confers on illegal aliens, the NYPD might understandably demur from testing the reach of its authority under the order.

So in Philadelphia, Bloomberg thumbed his nose at Congress yet again and dared that body to penalize him for violating the 1996 federal anti-sanctuary statute. New York would continue to ban its employees from reporting illegal aliens to the federal government, he said. The irony is that whenever anyone suggests allowing local law enforcement and other officials to cooperate with immigration agents, the open borders crowd responds that immigration enforcement is exclusively a federal responsibility. But how can federal agents discharge that responsibility when the people closest to the problem withhold needed information?

Mayor Bloomberg provided a valuable service with his testimony last week. He demonstrated that the belief that “no person is illegal”—watchword of the amnesty movement, popularized by Los Angeles Cardinal Roger Mahoney—will trump the willingness to enforce immigration laws every time. That’s why those who believe in the rule of law must insist on the “enforcement first” strategy for immigration reform: defer amnesty and the liberalization of immigration rules until border security and interior enforcement are demonstrably working. Mayor Bloomberg and President Bush’s “comprehensive” approach of combining amnesty and higher levels of immigration with a promise of increased enforcement will inevitably lose its second half along the way.