(CNN) Federal prosecutors and investigators are in disagreement over the strength of evidence in the investigation of the 2014 death of Eric Garner, stalling efforts so far to bring charges in the case, law enforcement officials briefed on the case tell CNN.

As recently as three months ago, the Justice Department Civil Rights Division in Washington appeared close to announcing charges, law enforcement officials briefed on the probe said.

Demonstrators rally against police brutality in memory of Eric Garner on Staten Island in 2014.

But objections from several officials overseeing the case, including from the U.S. Attorney's Office in Brooklyn and the FBI, have at least temporarily shelved those plans.

A Justice Department spokeswoman said the investigation is still ongoing and no decisions have been made.

Federal prosecutors in recent months have been using a grand jury in Brooklyn as part of their probe, CNN has previously reported. The focus of the investigation has been on whether NYPD officer Daniel Pantaleo used excessive force and broke the law in trying to arrest Garner for selling untaxed cigarettes.

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Pantaleo was shown on video, recorded by a bystander, using what witnesses said appeared to be a chokehold technique during the Garner takedown. The NYPD bans the use of chokeholds. Garner could be heard saying "I can't breathe" in the video, a phrase that became rallying cry for street protesters in the wake of a spate of police-involved deaths.

Pantaleo's attorney, Stuart London, said: "I've never thought any federally protected constitutional right was ever violated. This was a simple street encounter with no specific intent to ever violate his civil rights. It is very frustrating for my client to have this cloud still remain."

The Justice Department investigation in Garner case has faced numerous hurdles. New York state law provides immunity to anyone who testifies to a grand jury, which meant that the FBI agents and prosecutors working the case had to take extra steps to gather evidence for their probe.

Photos: Protests after Eric Garner grand jury decision Photos: Protests after Eric Garner grand jury decision Los Angeles Lakers' Kobe Bryant, center, warms up before an NBA basketball game against the Sacramento Kings on Tuesday, December 9, in Los Angeles. The team wore "I Can't Breathe" shirts during warm-ups in support of the family of Eric Garner. Since a grand jury declined to indict a New York police officer in the death of Garner, demonstrators across the country have taken to the streets to express their outrage. Garner, a 43-year-old asthmatic, died in July after he was put in a chokehold by the officer, Daniel Pantaleo. Hide Caption 1 of 31 Photos: Protests after Eric Garner grand jury decision Protesters gather in front of the Barclays Center during an NBA game in New York on Monday, December 8. Hide Caption 2 of 31 Photos: Protests after Eric Garner grand jury decision Police clash with demonstrators at the entrance of a Target near the Barclays Center on December 8. Hide Caption 3 of 31 Photos: Protests after Eric Garner grand jury decision Seven-year-old Elijah Owens, left, stands by people participating in a "die-in" demonstration outside the Philadelphia Eagles' stadium in Philadelphia on Sunday, December 7. Hide Caption 4 of 31 Photos: Protests after Eric Garner grand jury decision People protest in the streets of Chicago on December 7. Hide Caption 5 of 31 Photos: Protests after Eric Garner grand jury decision Demonstrators retreat in Berkeley, California, after police deploy tear gas during a protest that turned violent before dawn on December 7. Hide Caption 6 of 31 Photos: Protests after Eric Garner grand jury decision A police officer in Berkeley clashes with a protester on December 7. Hide Caption 7 of 31 Photos: Protests after Eric Garner grand jury decision A police officer raises a shotgun toward the crowd in Berkeley on Saturday, December 6. Hide Caption 8 of 31 Photos: Protests after Eric Garner grand jury decision People in Los Angeles lie down during a "die-in" on Hollywood Boulevard on December 6. Hide Caption 9 of 31 Photos: Protests after Eric Garner grand jury decision Police stand guard as protesters participate in a "die-in" December 6 at Grand Central Station in New York. Hide Caption 10 of 31 Photos: Protests after Eric Garner grand jury decision Protesters shut down all eastbound and westbound lanes on Interstate 195, which links Miami Beach to the mainland, on Friday, December 5. Hide Caption 11 of 31 Photos: Protests after Eric Garner grand jury decision Demonstrators march through the Loop in Chicago on December 5. Hide Caption 12 of 31 Photos: Protests after Eric Garner grand jury decision Protesters block an intersection in downtown Washington on December 5. Hide Caption 13 of 31 Photos: Protests after Eric Garner grand jury decision Demonstrators march through a Macy's in Manhattan before staging a "die-in" at the iconic department store on December 5. Hide Caption 14 of 31 Photos: Protests after Eric Garner grand jury decision Police make an arrest as protesters march through Manhattan early on December 5. Hide Caption 15 of 31 Photos: Protests after Eric Garner grand jury decision Police officers form a line with demonstrations under way in Oakland, California, on Thursday, December 4. Hide Caption 16 of 31 Photos: Protests after Eric Garner grand jury decision A demonstrator gets arrested during a protest in New York on December 4. Hide Caption 17 of 31 Photos: Protests after Eric Garner grand jury decision Police detain a protester in New York on December 4. Hide Caption 18 of 31 Photos: Protests after Eric Garner grand jury decision Demonstrators gather in New York's Foley Square on December 4. Hide Caption 19 of 31 Photos: Protests after Eric Garner grand jury decision Police officers in New York staff a barricade at a Brooklyn Bridge exit ramp on December 4. Hide Caption 20 of 31 Photos: Protests after Eric Garner grand jury decision Demonstrators march across the Brooklyn Bridge on December 4. Hide Caption 21 of 31 Photos: Protests after Eric Garner grand jury decision "Black Lives Matter" is written across the cheek of Samaria Muhammad as she chants with fellow protesters in Atlanta on December 4. Hide Caption 22 of 31 Photos: Protests after Eric Garner grand jury decision Demonstrators block the entrance to the Lincoln Tunnel in New York on Wednesday, December 3. Hide Caption 23 of 31 Photos: Protests after Eric Garner grand jury decision Protesters lie down in Grand Central Station on December 3. Hide Caption 24 of 31 Photos: Protests after Eric Garner grand jury decision A demonstrator cries at a protest in Philadelphia on December 3. Hide Caption 25 of 31 Photos: Protests after Eric Garner grand jury decision Demonstrators block traffic on Interstate 395 in Washington on December 3. Hide Caption 26 of 31 Photos: Protests after Eric Garner grand jury decision A woman speaks during a demonstration in Oakland on December 3. Hide Caption 27 of 31 Photos: Protests after Eric Garner grand jury decision Police officers stand guard in New York's Times Square on December 3. Hide Caption 28 of 31 Photos: Protests after Eric Garner grand jury decision Protesters rally near Rockefeller Center during a ceremony to light the Rockefeller Center Christmas Tree in New York. Hide Caption 29 of 31 Photos: Protests after Eric Garner grand jury decision Protesters face off with police in Oakland. Hide Caption 30 of 31 Photos: Protests after Eric Garner grand jury decision Demonstrators lie in the streets of St. Louis on December 3. Hide Caption 31 of 31

And another complication is a dispute of whether Pantaleo used a chokehold, and if so for how long and whether it was enough force to kill Garner. Some officials involved in the case believe the evidence evidence is not conclusive.

Cases like this are notoriously hard ones to make and relatively few result in federal civil rights charges against a police officer, law enforcement officials said.

Some officials led by Brooklyn U.S. Attorney Robert Capers and FBI agents investigating the case have advised superiors that there isn't enough evidence to bring charges, the law enforcement officials said.

In a statement to CNN, Justice Department spokesperson Dena Iverson said, "The Garner investigation is being handled in a manner similar to many of our civil rights investigations, where experienced prosecutors from both the U.S. Attorney's office and the Civil Rights Division jointly investigate the case. In every single case the department brings -- including civil rights matters -- the department reaches one decision regarding whether charges can responsibly be brought at the conclusion of the investigation. The investigation into the death of Eric Garner is active and ongoing and no decisions have been made regarding the outcome of the case."

A spokeswoman for the FBI declined comment. A spokeswoman for the Brooklyn U.S. Attorney didn't comment.

One official involved in the matter said disputes over the strength of a case are a normal part of discussions before deciding whether to bring charges. "That's how we test the strength of our cases," the official said.

Last year, a New York state grand jury declined to charge Pantaleo in a separate case investigated by the Staten Island district attorney.

In cases of alleged police misconduct, state laws offer more broad authority to bring charges. Federal charges are considered a fall back because federal law has much narrower jurisdiction.