Kathryn Elaine "Kate" Peterson was an inmate who appeared from episodes 235-273, she was a former doctor

who was sentenced for killing her husband, she was one of the characters who went from good to bad, she later goes mad and murders inmate Sandy Edwards and was sent to a mental hospital after a murder attempt on her cell mate Judy Bryant.

Arrival At WentworthEdit

Dr Kate Peterson entered Wentworth as a prisoner at the same time as prisoner Sandy Edwards, episode (235). She also shared the same charge as Sandy.

Kate and Sandy were shown in the van prior to their arrival - while most new characters appear in the reception. Kate was shown to be timid and anxious, completely out of her depth. During their trip to Wentworth, Kate and Sandy bond and become genuine friends, despite being from very different backgrounds. Kate explains that she killed her lover Conrad because he was threatening her son. She also reveals to Sandy that prison life is completely foreign to her, and Sandy promises to help Kate. Fortunately for them, they were placed in the same cell.

Kate found adjusting to her new lifestyle difficult and was assertively standing up to the officers for rights she felt she deserved. Despite being insubordinate, she is allowed to work in the hospital as an aide for the Sister. At the same time, Bea Smith was becoming ill and retreated from the top dog position; leaving it open for an ambitious and opportunistic Sandy. Despite asserting her view that violence solves nothing, because she relied on Sandy as her friend and guardian, Kate got caught up in the middle of the top dog turf war, being attacked by Judy Bryant, Hazel Kent and Doreen Anderson. When Sandy retaliates on her behalf, Kate realizes that violence speaks louder than words in Wentworth.

Kate found herself on the wrong side of the fence when she tells the Governor her concerns about a fellow prisoner, which the other prisoners thought of as "lagging." When Kate correctly diagnozes Bea's illness as a kidney ailment, she is able to gain crucial ground again. Kate gets a visit from her mother, and it is revealed that she is far more cunning, devious and ruthless than she had been making out. Kate reveals that she in fact killed Conrad because he threatened to expose the fraud of the health service at Kate's practice, explains that she has been fooling the women all along, and admits that she sees her son as little more than a tool to gain favour with the judge. We witness her Jekyll and Hyde personality sporadically, such as being friendly and sweet to Lizzie Birdsworth and muttering insults about her when she has gone. 

When Bea Smith was sent to hospital for treatment, Marie Winter arrived, which would cause potential problems for Sandy. Marie did not try to usurp Sandy's position but instead coerced her into causing a riot and taking over the prison, whilst a calculating and scheming Kate watched on from the sidelines. After the riot failed and Sandy was discredited, Marie took over as top dog. Whilst under the pretense of supporting Sandy, Kate began to set up lagging sessions with ambitious officer Colleen Powell, in return for secret visits with Inspector Grace. Kate lagged on other prisoners and their illicit activities, particularly Sandy, to Grace with the agreement that she would receive a false witness to perjure themselves in her favour at her hearing. Whilst in hospital, Bea Smith is told by a former colleague of Kate's about the "real" Kate Peterson; painting her to be a cold, greedy and ruthless woman.

Lagger Edit


Kate's file

Kate began bonding with Marie, seeing potential gain in a partnership with her. A deceitful act by Kate and Marie lead Sandy's husband to be killed by the gang she was dealing with. When Sandy killed Marie's drug supplier in turn, Marie was offered a reward to kill Sandy. To do this, Marie convinced Kate to play on her faux friendship with Sandy and drug her, then send her to the shower block, where Marie attempted to kill Sandy but was stopped by Doreen. Eventually, Sandy and a recently returned Bea worked around to the fact that somebody was lagging on them. In the end, a suspicious Sandy fed false information to Kate, who in turn fed it to Grace, which outlined Kate as the lagger.

Sandy was repeatedly telling Kate that she would kill the person who was lagging on them, and was implying strongly that she knew it was Kate. To protect herself, Kate then tried to poison Sandy, however, Sandy was prepared and forced Kate to drink the poison instead. Kate did reach the antidote in time, however, this only served to prove to Sandy that Kate tried to kill her. Kate realized she had run out of luck, however, a skeptical governor and unsympathetic Colleen Powell dismissed her claims that she was in danger. Marie, seeing laggers as the scum of the Earth, also had reason to kill Kate. After the failed attempt at murdering Sandy, Kate had a confrontation with Marie in Marie's cell, where an argument between Kate and Sandy started and ended with Kate spewing out some of the most hilarious insults to Marie, Sandy and Marie ended up sabotaging each other's attempts to kill her, and decided to play a game of cards to determine who would kill her, with support from the other; Sandy drew the winning card.

Suspect For Murdering Sandy Edwards Edit

Sandy planned to kill Kate behind the dumpster when the two were to be emptying bins before the garbage truck arrived. Marie started a riot and Sandy revealed her intentions to Kate. However, it was not Sandy who returned from the meeting, but Kate, much to the shock of all the prisoners. Exactly what happened was never revealed; Sandy had completely disappeared, and nobody knew what happened to her. Around this time, Kate began acting strangely, sparodically exhibiting symptoms of psychosis. When Marie discovered Kate with the knife Sandy had taken from her, she realised the very strong possibility that Kate had somehow incapacitated Sandy and dumped her body in the dumpster as the crusher truck was doing its rounds. Kate repeatedly denied that she had anything to do with Sandy's disappearance. Marie made several attempts at Kate's life, all of which were narrowly thwarted. Kate was living in constant fear for her life and it paid a heavy toll on her mental well being. At the same time, Inspector Grace revealed he had used her information and added a charge of conspiring to pervert the course of justice with a false witness. Realizing she had finally been outsmarted, Kate threatened to kill Grace and attacked him, but was taken away. At her appeal, Kate plead not guilty to all charges. Unfortunately for her, she was found guilty of all charges and sentenced to ten years in Wentworth prison, after furiously insulting the judge, the jury and the barristers. Kate seemed to legitimately believe she was innocent. 

When Kate returned, she found the women had organised a trial for her of their own; in which Kate was tried for lagging to the police, lagging to the screws and the murder of Sandy Edwards - the judge was a dummy dressed up in Sandy's clothes. Kate was unanimously voted guilty and Marie was appointed the executioner. Kate was desperate for a way out, and was ecstatic to hear she would be transferred to Barnhurst. As Kate gloated about escaping from Wentworth and its murderers, she was introduced to the other prisoner making the trip with her; Marie Winter. Kate refused to get in the van and assaulted an officer; thus remaining at Wentworth. When Kate demanded protection from the other women, officer Fawkner, who had been romantically linked with Sandy, told her to admit to Sandy's murder and be transferred, but Kate adamantly denied having anything to do with Sandy's disappearance.

Becoming Insane Edit

In the succeeding episodes, Kate's suspected madness began to escalate rapidly. Her personality began to change and she seemed to genuinely believe she was at Wentworth for no reason other than to treat the other patients. She attempted to start a business partnership with Erica Davidson to the confusion of the staff. Helen Smart spoke to Kate and Kate opened up about her misdeeds, getting the murders of Sandy and Conrad confused and admitting she put somebody in the garbage compactor to save her own life. The women began to get concerned about their own safety after Kate quickly subdued and choked Margo Gaffney for what Kate perceived as being rude to her.

In an attempt to bridge the gap between Kate and the other women, Erica Davidson put Judy and Kate in the same cell. Kate believed that Judy's purpose there was to protect her, and when Judy refused, Kate stayed up the entire night with a blank, psychopathic gaze fixed on Judy. The next day, Kate attempted to strangle Judy to death, believing Judy to be part of a grand scheme to destroy her, and claimed she was going to take the women down one by one, but was thwarted by Bea Smith and Steve Fawkner and sent to solitary. There, Kate experienced a complete mental breakdown and spent the night with violent and loud reactions to hallucinations, resulting in being restrained by the officers for her own safety. The next day, Kate was diagnosed with psychosis and schizoid tendencies, and was transferred to a mental institution in episode (273), and it was believed she might never recover. She was never heard of again. Her last mention was in 379 by Lizzie in a conversation with Pixie Mason.