Rhianna is prepared to testify at Chris Brown’s preliminary hearing today, which would mark the first time she publicly tells her side of what happened the night her boyfriend allegedly assaulted her, CNN reports. The star may be questioned by Brown’s attorney, Mark Geragos, about the couple’s Grammy-night argument in a rented Lamborghini that, according to charges, turned violent. Though Geragos has said he wanted to avoid a public trial, plea-deal talks failed and a judge last week rejected his request to delay the hearing. The 20-year-old Brown pleaded “not guilty” to felony counts of assault and making criminal threats; he could face up to four years and eight months in prison if convicted. Cameras will not be allowed in today’s hearing, which determines whether there is enough evidence against Brown to go to trial.