Rihanna and Chris Brown

He allegedly bruised and battered her, yet she took him back. And now, could she get him off the hook?

Legal experts say whether Rihanna will testify against Chris Brown could be a key factor in his felony case.

“The DAs are facing an uphill battle now if Rihanna isn’t cooperating,” says Steve Sitkoff, a Los Angeles defense lawyer and former prosecutor. “At this point, her cooperation can make or break the case. But the DAs may not need her if Brown is willing to strike a plea deal.”

Brown was formally charged Thursday with two felonies – assault and making criminal threats. If convicted, he faces anywhere from probation to a maximum four years and eight months in state prison, prosecutors say.

Asked if Rihanna is cooperating with the DAs, her lawyer Donald Etra said: “She’ll do everything that the law requires her to do.”

Experts say prosecutors will almost certainly subpoena Rihanna as a witness, but while she may be forced to appear she cannot be threatened with jail time – as is possible in a non-domestic violence case – if she refuses to take the stand.

At most, she could be punished with fines or other sanctions, but a judge may be reluctant to do so.

“If she refuses to testify, that could potentially jeopardize the DA’s case,” says Loyola Law School professor Stan Goldman. “Her statements to police about Brown having beaten her can only be used against him if she agrees to testify.”

Experts agree it’s just too soon to tell.

“Rihanna and Brown obviously have a volatile relationship,” says L.A. defense attorney and former prosecutor Jeffery Rubenstein. “Who knows if they’ll be together tomorrow. She may want him to take responsibility for his actions and take the stand. This case has only just begun.”