Washington (CNN) -- A heckler standing just behind Barack Obama in San Francisco this week yelled to the President that he "has the power to stop deportation."
A clearly irritated Obama interrupted his speech and shot back that he doesn't have that authority, saying the United States is "a nation of laws."
So, who's right?
Federal immigration law provides for the deportation, or removal, of an individual under several circumstances -- including being in the country illegally, overstaying a legal visa, violation of criminal statutes or a number of other offenses — after a judicial process.
But the administration has latitude in how to enforce those laws, though legal experts say exercising that discretion too broadly is fraught with political and legal land mines.
Ju Hong, the 24-year old heckler, is a University of California, Berkeley graduate and a member of Asian Students Promoting Immigrant Rights Through Education, ASPIRE.
After the event on Monday at a community center, the group insisted the President can use his executive authority to halt deportations.
Hong and his group want Obama to stop all deportations, which they say creates a culture of fear among undocumented immigrants and breaks up families.
Obama spokesman Josh Earnest pushed back, saying the President does not have that authority. "As I think the President said rather definitively, there is also not an executive action that would address all of the concerns that that young man had raised," said Earnest Tuesday from Los Angeles.
But that doesn't convince May Liang, an organizer for ASPIRE. She told CNN Tuesday that she still thinks Obama "blatantly lied" when he said he didn't have the power to stop deportations. In a statement Monday, the group asked him for his "legal analysis" of why he can't stop deportations.
Obama, however, stood firm.
"The easy way out is to try to yell and pretend like I can do something by violating our laws," Obama told Hong Monday.
"And what I'm proposing is the harder path, which is to use our democratic processes to achieve the same goal that you want to achieve. But it won't be as easy as just shouting. It requires us lobbying and getting it done," he said.
Obama told Univision In January that he's "required to follow the law," which makes it a misdemeanor to be in the country illegally. Those found guilty can be deported.
But the President has exercised discretion on deportations in the past.
In 2012, he announced that the Department of Homeland Security's Immigration and Customs Enforcement was not going to deport Dreamers, children of undocumented immigrants.
And in August, he announced that parents would not deport parents caring for children.
But still, he has been aggressive on that front. Obama has deported more people than any other president. For instance, 410,000 people were deported in 2012 compared to 116,000 in 2001.
Obama has shifted the type of immigrants targeted for deportation. While the administration of President George W. Bush targeted working immigrants by raiding workplaces, Obama is focusing on convicted criminals and "egregious" immigration violators, including recent border crossers and illegal re-entrants.
Immigration and Customs Enforcement said 55% of people deported last year were convicted criminals.
Richard A. Boswell, immigration law professor at the University of California's Hastings College of the Law, said the President is "partially correct."
It's called prosecutorial discretion. The executive branch has the "inherent power to choose which cases to act on," Boswell said.
Think of the police. They can theoretically give someone driving four miles over the speed limit a ticket, but the police officer also has the ability to use discretion to give a warning instead.
That's the validation Obama used in his decision to halt deportations of youth and parents.
But Philip Schrag, professor of public interest law at Georgetown Law School, said the President's position is that putting an end to all deportations would "abuse" his discretion.
Immigration law attorney Austin Gragomen said he thinks Obama "has an obligation to enforce the law" even if he chooses how and to what extent to enforce it.
Boswell disagreed. He said the President can use his discretion to hold deportations.
The President is "making a tactical political move to force Congress to act. He could just as easily told Congress that he would withhold deportations on broad categories of cases pending their action," Boswell wrote in an e-mail.
The Senate passed comprehensive immigration reform earlier this year, which includes a path to citizenship for the 11 million undocumented immigrants already in the United States.
The legislation has been stalled in the House and is unlikely to be taken up before the end of the year.
The issue of deportations hasn't just upset immigration advocates. The top Republican on the House Judiciary Committee, Rep. Bob Goodlatte, R-Virginia, announced he would hold a hearing on the issue to investigate the President's decision to not deport some people.
The hearing is titled, "The President's Constitutional Duty to Faithfully Execute the Laws."