A woman found guilty of murdering her boyfriend should have her conviction overturned because the trial failed to include evidence of her mental health, the court of appeal has heard.

Emma-Jayne Magson, 26, of Sylvan Street, Leicester, was found guilty of killing 26-year-old James Knight with a single stab wound to the heart in March 2016 after a drunken row. She was sentenced to life imprisonment at Leicester crown court in November 2016.

The court of appeal heard that the conviction was unsafe because evidence about her mental health was not put before the trial jury.

Magson’s lawyers told three senior judges that fresh psychiatric evidence suggested the defendant may have been suffering from diminished responsibility at the time of the killing.

Opening Magson’s appeal in London on Tuesday, Clare Wade QC said Magson suffered from emotionally unstable personality disorder (EUPD), which she said “lay in the appellant having endured a childhood which was characterised by exposure to domestic violence”, as well as “parental neglect” and being bullied at school.

She said Magson had stabbed Knight after he had been kicking at her front door “in circumstances where the deceased had been violent to her earlier in the evening”. Wade described their relationship as volatile.

She submitted that Magson’s condition “substantially impaired her ability to exercise self-control and that the EUPD provides an explanation for her conduct and was a significant contributory factor causing the applicant to stab the deceased”.

Wade told the court the evidence meant it was “more likely than not that, at the time of the offence, the appellant was suffering from diminished responsibility”.

Wade said psychiatric experts who had been instructed before Magson’s trial now agreed “that the appellant’s EUPD was the result of her childhood experiences which included exposure to domestic violence”.

She added that the experts also agreed that “the defence of diminished responsibility … would have been available to her”.

Wade told the senior judges that Magson was unable to participate fully in her trial, saying her “impoverished verbal reasoning skills, EUPD and social communication difficulties” had compromised her ability to properly instruct her lawyers.

Speaking outside the Royal Courts of Justice before the appeal, Magson’s mother, Joanne Smith, said: “I feel sick. Nervous, very nervous. I’ve had two hours’ sleep.”

Smith said the case of Sally Challen, whose murder conviction against her abusive husband was overturned by the court of appeal earlier this year, had brought issues around domestic violence “to the surface”.

Magson is one of two high-profile cases this year, the other being that of Farieissia Martin, where women are appealing against their murder convictions. Last week, Martin won the first stage of an attempt to overturn her murder conviction.

Smith added: “I think people are starting to realise that abuse is not just black eyes and broken bones.”

Challen’s son, David, who was also outside court prior to the hearing, said there had been a “definite shift in our understanding as a society of the mental impact victims of abuse suffer”.

He added that it was “important to stand with other victims” of domestic abuse and male violence.

William Hughes QC is opposing Magson’s appeal on behalf of the prosecution.

Lord Justice Fulford, Mr Justice William Davis and Mr Justice Johnson will hear Magson’s appeal over a full day.

The hearing continues.