American R&B singer Chris Brown has faced multiple legal episodes throughout his career. Notably, he pleaded guilty to assaulting his then-girlfriend Rihanna in 2009, resulting in a sentence of five years' probation, community service, and mandatory domestic violence counseling. In addition to this incident, Brown has been accused of other acts of physical assault and has also faced dismissed rape allegations, for which he countersued for defamation.

At around 12:30 a.m. (PST) on February 8, 2009, Brown and his then-girlfriend, singer Rihanna, had an argument which escalated into physical violence, leaving Rihanna with visible facial injuries which required hospitalization. Brown turned himself in to the Los Angeles Police Department's Wilshire station at 6:30 p.m. (PST) and was booked under suspicion of making criminal threats. The police report did not name the female in the incident as is policy, but media sources soon revealed that the victim was Rihanna. Following Brown's arrest, several commercial ads and some TV shows featuring him were suspended, his music was withdrawn from multiple radio stations, and he withdrew from public appearances, including one at the 2009 Grammy Awards, where he was replaced by Justin Timberlake and Al Green. Brown hired a crisis management team and released a statement saying, "Words cannot begin to express how sorry and saddened I am over what transpired." On February 19, 2009, a graphic photo of Rihanna's battered face was leaked online, reportedly taken after her assault by Chris Brown on February 8. The image, showing bruises, swelling, and a split lip, was first published by TMZ and quickly circulated across media outlets and social platforms, sparking widespread public outrage. The Los Angeles Police Department initiated an internal investigation into the unauthorized release of the photo, considering it a serious misconduct with potential penalties up to termination. Despite this, no criminal charges were filed against the officers involved due to insufficient evidence.

On March 5, 2009, Brown was charged with felony assault and making criminal threats. He was arraigned on April 6, 2009, and pleaded not guilty to one count of assault and one count of making criminal threats. On June 22, 2009, Brown pleaded guilty to a felony and accepted a plea deal of community labor, five years of probation, and domestic violence counseling. Several organizations against domestic violence criticized the plea deal, advocating the punishment was not severe enough for the crime; the level of Brown's influence over youth also came under scrutiny. On July 20, 2009, Brown released a two-minute video on his official YouTube page apologizing to fans and Rihanna for the assault, expressing the incident as his "deepest regret" and saying that he has repeatedly apologized to Rihanna and "accepts full responsibility". In the video, Brown said he wanted to speak out earlier about the case but was advised by his attorney not to until the legal ramifications were settled. On August 25, Brown received five years of probation. He was ordered to attend one year of domestic violence counseling and undergo six months of community service; the judge retained a five-year restraining order on Brown, which required him to remain 50 yards (45.72 meters) away from Rihanna, reduced to 10 yards at public events. Andy Kellman of AllMusic stated, "A fairly substantial backlash resulted in Brown's songs being pulled from rotation on several radio stations. Ultimately, however, it had little bearing on the progress of his music and acting careers."

On September 2, 2009, Brown spoke about the domestic violence case in a pre-recorded Larry King Live interview, his first public interview about the matter. He was accompanied to the interview by his mother, Joyce Hawkins, and attorney Mark Geragos, as he discussed growing up in a household with his mother being repeatedly assaulted by his stepfather. Brown said of hearing details of his assault of Rihanna, "I'm in shock, because, first of all, that's not who I am as a person, and that's not who I promise I want to be." Brown's mother said Brown "has never, ever been a violent person, ever" and that she does not believe in the cycle of violence. Brown said that it is "tough" for him to look at the famous photograph released of Rihanna's battered face, which may be the one image to haunt and define him forever, and that he still loved her. "I'm pretty sure we can always be friends," said Brown, "and I don't know about our relationship, but I just know definitely that we ended as friends." He stated he did not feel that his career was over, and likened his relationship with Rihanna to Romeo and Juliet, blaming the media attention in the aftermath of the assault for driving them apart. When asked if he had any memory of assaulting Rihanna, he said that he did not, but realized that it occurred, and was sorry for his actions. However, following criticism of saying he did not remember, he later said in a statement, "Of course I remember what happened. Several times during the interview, my mother said that I came to her right afterwards and told her everything." Brown said despite this, "[that night] was and still is a blur".

In June 2010, Brown's application for a visa to enter the UK was rejected on the grounds of him "being guilty of a serious criminal offence" due to his assault on Rihanna. Brown had been planning to do a tour of British cities as part of a European tour but Sony stated that due to "issues surrounding his work visa" the tour was to be postponed. In February 2011, at the request of Brown's lawyer, Judge Patricia Schnegg modified with Rihanna's agreement the restraining order to a "level one order," allowing both singers to appear at awards shows together in the future. The following month, on March 22, 2011, during an interview with Robin Roberts on Good Morning America at the Times Square Studios, where he was repeatedly asked about the Rihanna situation and restraining order, Brown became violent in his dressing room during a commercial break before his second performance ending that day's program, and punched a window overlooking Times Square, causing damage to it. He then took off his shirt, and after angry confrontations with the show staff and building security, left the building shirtless. The following day, he apologized during live appearance on BET's "106 & Park": "First of all, I want to apologize to anybody who was startled in the office, or anybody who was offended or really looked, and [was] disappointed at my actions, because I'm disappointed in the way I acted".

On July 11, 2012, Brown's community service was evaluated and he was ordered to meet a judge. The evaluation was ordered by Superior Court Judge Patricia Schnegg on July 10, 2012. He was scheduled to appear in court with regard to the evaluation on August 21, 2012. While conducting his community service in Virginia, however, Brown was tested positive for cannabis and appeared in court on September 25, 2012, at which time his hearing date was changed to November, to determine whether or not he had violated the terms of his court order. He reappeared in court on November 1, 2012, and attempted to speak to the judge, but his lawyer, Mark Geragos, told him, "I don't dance; you don't talk." On March 20, 2015, Brown's probation ended, formally closing the felony case emanating from the Rihanna assault which happened over six years prior.

In his 2017 self-documentary Welcome to My Life, Brown opened up about his relationship with Rihanna and the events surrounding their 2009 altercation. Brown described their relationship as initially a "fairytale" but explained that it deteriorated after he admitted to being unfaithful with a woman who worked for him, leading to a loss of trust. He stated, "My trust totally was lost with her. She hated me after that … From there, it just went downhill". Brown recounted the night of the violent altercation. He described how an argument escalated after Rihanna found a text message on his phone from the former employee, leading to a physical altercation in a car. Brown then provided a description of the fight, admitting that Rihanna tried to kick him before he punched her, injuring her lip. He recalled feeling shocked afterward, and described the altercation as a heated, escalating fight that took place while they were driving. Reflecting on the incident and its aftermath, Brown addressed the widely circulated photograph of Rihanna’s injuries, saying, "I look back at that picture and I’m like: ‘That’s not me, bro, that’s not me. I hate it to this day. That’s going to haunt me forever.’" He admitted that after the assault, he "felt like a f–king monster" and acknowledged the incident dramatically changed his public image. Brown also addressed how witnessing domestic violence during his childhood affected his own behavior. He acknowledged that exposure to his mother’s partner’s abusive actions played a role in the 2009 incident involving Rihanna, describing it as “learned behavior.”

On June 14, 2012, Drake and his entourage were involved in a scuffle with Brown at a nightclub called WIP in the SoHo neighborhood of New York City. About eight people were injured during the brawl, including San Antonio Spurs star Tony Parker, who had surgery to remove a piece of glass from his eye. Drake was not arrested. Brown's attorney alleged Drake was the instigator. Brown himself tweeted about the incident and publicly criticized Drake weeks later.