Updated, 1:28 p.m.

The Supreme Court this morning rendered a split decision on Arizona’s immigration enforcement law, upholding some police powers while striking down state criminal penalties.

In a 5-3 ruling written by Justice Anthony Kennedy, the Supreme Court upheld the provision of S.B. 1070 that allowed law enforcement officers to check the immigration status of people whom they suspect of being in the country illegally, the “papers please” provision, as critics have dubbed it.

But the justices struck down most other parts of the law, such as provisions that made it a state crime for undocumented immigrants not to have identification, work or apply for work, as well as a provision that allowed law enforcement officers to arrest without a warrant undocumented immigrants suspected of committing crimes that would lead to their deportation.

Justice Antonin Scalia, in a dissenting opinion, ripped President Barack Obama’s executive action to end deportations of as many as 1.4 million young illegal immigrants who came to the United States as children.

Scalia wrote that conserving resources can’t be a justification for Obama’s action, given that the administrative costs of background checks and ruling on requests for dispensation “will necessarily be deducted from immigration enforcement.”

He added, “To say, as the Court does, that Arizona contradicts federal law by enforcing applications of the Immigration Act that the President declines to enforce boggles the mind.”

Democrats and Republicans declared partial victories.

Obama issued a statement saying he was “pleased that the Supreme Court has struck down key provisions of Arizona’s immigration law.” But he said the decision makes it clear that Congress needs to act on a broad immigration reform measure. “A patchwork of state laws is not a solution to our broken immigration system — it’s part of the problem,” Obama said.

The president warned, however, that federal officials would be monitoring Arizona law enforcement to ensure it does not use the ID provision that the court upheld to racially profile Hispanics.

“Going forward, we must ensure that Arizona law enforcement officials do not enforce this law in a manner that undermines the civil rights of Americans, as the Court’s decision recognizes,” Obama said.

He reiterated that he would continue to prioritize immigration enforcement to focus on security threats and criminals “and not, for example, students who earn their education — which is why the Department of Homeland Security announced earlier this month that it will lift the shadow of deportation from young people who were brought to the United States as children through no fault of their own.”

For his part, presumptive GOP presidential nominee Mitt Romney issued a vague statement that criticized Obama for failing to push immigration reform in his first term.

“Today’s decision underscores the need for a President who will lead on this critical issue and work in a bipartisan fashion to pursue a national immigration strategy. President Obama has failed to provide any leadership on immigration. This represents yet another broken promise by this President. I believe that each state has the duty — and the right — to secure our borders and preserve the rule of law, particularly when the federal government has failed to meet its responsibilities. As Candidate Obama, he promised to present an immigration plan during his first year in office. But 4 years later, we are still waiting.”

During the primaries, Romney said Arizona is “a model” for the nation when it comes to immigration. But while many have interpreted that to mean a strong endorsement for S.B. 1070 from the former Massachusetts governor, the Romney campaign has said he was referring to the state’s e-verify system to check employment eligibility, not the more controversial law on detention of suspected illegal immigrants.

Senate Majority Leader Harry Reid (D-Nev.) said the decision striking down three of the law’s four major provisions shows that the Obama administration was right to challenge it in court.

“I am greatly concerned that the provision putting American citizens in danger of being detained by police unless they carry their immigration papers at all times will lead to a system of racial profiling,” he said. “This is a strong reminder that ultimately, the responsibility for fixing our nation’s broken immigration system lies with Congress.”

Reid also called it “disturbing” that Romney called the law a “model.”

“Laws that legalize discrimination are not compatible with our nation’s ideals and traditions of equal rights, and the idea that such an unconstitutional law should serve as a ‘model’ for national reform is far outside the American mainstream,” Reid said.

“This decision tells us that states cannot take the law into their own hands and makes it clear that the only real solution to immigration reform is a comprehensive federal law,” said Sen. Charles Schumer (D-N.Y.).

Arizona’s two Republican Senators, Jon Kyl and John McCain, issued a joint statement saying they want to fully review the decision.

“The Arizona law was born out of the state’s frustration with the burdens that illegal immigration and continued drug smuggling impose on its schools, hospitals, criminal justice system and fragile desert environment, and an administration that chooses to set enforcement policies based on a political agenda, not the laws as written by Congress,” they wrote. “We will continue our efforts on behalf of the citizens of Arizona to secure our southern border. We believe Arizonans are better served when state and federal officials work as partners to protect our citizens rather than as litigants in a courtroom.”

Arizona Gov. Jan Brewer (R) also declared victory, saying the court had upheld “the heart” of the law.

“Today’s decision by the U.S. Supreme Court is a victory for the rule of law. It is also a victory for the 10th Amendment and all Americans who believe in the inherent right and responsibility of states to defend their citizens,” she said.