The Santa Clara County District Attorney's Office says it is "close" to deciding whether to file assault charges against 49ers linebacker Ahmad Brooks but that the investigation has not yet been completed.

"The case is not done," Assistant District Attorney Karyn Sinunu-Towery said Wednesday. "And that's where we are."

Sinunu-Towery said a preliminary investigation was made following an incident between Brooks and teammate Lamar Divens on June 8. She said there was conflict in the district attorney's office over whether an arrest warrant should be issued � Divens decided not to press charges � and it was determined additional information was needed.

Some of that additional information, including medical statements, remained outstanding when the complaint against Brooks was sent to a judge last week. Sinunu-Towery said "an internal error" in the district attorney's office caused the case to be filed prematurely with the court.

According to those court documents, Brooks, Divens and two defensive teammates on the 49ers - Lawrence Okoye and Mike Purcell - had been drinking in San Jose on June 8 when they returned to Brooks' home in Brooks' truck.

After Divens, who had been driving, initially did not give Brooks the keys to the truck, Brooks hit him repeatedly over the head with a beer bottle, opening a gash that needed to be closed with stitches the documents said. Brooks also threatened to retrieve a gun from his home, according to court records.

Brooks, 29, was described in the police report as "very drunk." Officers who responded reported Divens, 27, did not show any outward signs of being intoxicated. Divens had been serving as the group's driver that night. Divens initially told police he would press charges but five days later changed his mind, telling police that doing so would be "bad for both of their careers."

In a statement released Wednesday morning, the 49ers said, "We are aware of the situation involving Ahmad Brooks. Out of respect for the legal process, the club will have no further comment at this time."

Brooks, who was accused of punching a woman in 2008 and reportedly accepted mediation on the charges, presumably faces discipline under an NFL policy that gives Commissioner Roger Goodell discretion in matters involving personal conduct. According to that policy, "discipline may take the form of fines, suspension, or banishment from the league." It's not yet known whether Goodell is reviewing Brooks' case.

Brooks has started every game for the 49ers for the last two years at left outside linebacker, and he had two pivotal plays at the end of the NFC Championship Game in Atlanta in January to preserve the win for the 49ers.

The 49ers have considerably more depth at outside linebacker than they did a year ago. Veteran Parys Haralson is healthy again after tearing his triceps tendon in August. The team also used a third-round draft pick on Corey Lemonier, who will compete with holdover Cam Johnson and free-agent acquisition Dan Skuta for playing time. Darius Fleming, a 2012 draft pick, has been moved from outside linebacker to inside linebacker.