Federal, state and local officials duke it out over Ferguson investigation

(CNN) -- Justice Department and FBI representatives have had a front-row seat to the St. Louis County investigation into the shooting death of Michael Brown in Ferguson, Missouri. They've participated on witness interviews and got full access to grand jury testimony and evidence.

But in the coming weeks, when local authorities announce the results of the investigation and a decision by the grand jury on possible charges against the police officer who killed him, don't expect federal authorities to be standing next to county prosecutor Robert McCulloch.

McCulloch has pushed for the federal officials to coordinate the completion of the separate federal civil rights investigation and to make a joint announcement, according to federal and local officials briefed on the discussions.

Local officials believe a united front would help reduce the potential for violence on the streets if the grand jury declines to bring charges against officer Darren Wilson.

Justice officials have rejected the idea, in part because they believe a joint announcement would undermine their argument that the federal investigation is independent.

State and federal investigations are focused on separate legal statutes, federal officials say. A Justice official says that the department "has informed the locals that the investigation will conclude when it's ready not on an artificial timetable."

If, as is widely expected, the St Louis County grand jury declines to bring charges, the Justice Department could announce it will review the state investigation to ensure it was done properly, according to the officials briefed on the matter.

Rising tensions between officials

Local officials bristle that the federal government could do another review. That's because the Justice Department and the FBI have sat through almost every interview, or have had access to transcripts from those interviews, according to government officials.

The tussle has heightened an already tense situation in discussions among local, state and federal officials. All are concerned about possible violence in the wake of the grand jury's decision. No one wants the blame.

The manner in which the local prosecutor has presented the case is somewhat unusual for St. Louis County.

Usually grand jury proceedings involve a couple of witnesses, but, in this case, there have been many more. And the prosecutor is presenting all evidence to the grand jury, including information that supports the account of Wilson. That's also unusual.

There is some cooperation between the federal and local investigators. The FBI performed some of the forensic tests that the state is using in its case.

Trying to heal a community-police rift

But as the investigation into the shooting has continued, federal and state officials, along with members of the Missouri congressional delegation, have been working on proposals to try speed reforms to improve a poor relationship between the Ferguson police and the mostly African-American community it is supposed to protect.

Among the those efforts is a plan in the works under which Thomas Jackson would step down as Ferguson police chief to make way for the St. Louis County Police Department to assume management of the smaller force, according to government officials briefed on the discussions.

CNN's report on those plans prompted pushback from city officials who already weren't pleased by state and federal officials push for rapid changes.

On Wednesday, Attorney General Eric Holder said in remarks at the Washington Ideas Forum: "I think it's pretty clear that the need for wholesale change in that department is appropriate."

Last month, the Justice Department publicly released a letter it sent to the Ferguson Police to prohibit city officers from wearing on-the-job wristbands with the words "I am Darren Wilson." Justice Department officials have also expressed anger at leaks that they blame on local authorities trying to manage the public perception of the case.

Another point of contention could come at the end of the grand jury process, when local officials want to immediately release all evidence that was part of their investigation.

If federal officials are still conducting their investigation, they may oppose the release of sensitive information.