Joanna Martin KC

Background

Solicitor: 1996
Called to the Bar: 2005
Took silk: 2018

Practice areas

Serious crime
Regulatory crime
Financial crime (fraud)
Complex fact finds in family cases

What others say

‘Jo is always prepared and thinks deeply about her cases. She is always trusted by a jury and well-regarded as a silk of real ability and dedication.’

Legal 500 2025 Leading Silks

‘Jo is superb; very thoughtful, determined and charming as an advocate – one of those in whom juries place their trust. She is always beautifully prepared and brings a lightness of touch to her advocacy which is compelling.’

Legal 500 2024 Leading Silks

‘Joanna works extremely hard and is always completely on top of instructions. She is very friendly and dynamic; she leads any team well. She inspires confidence in others and has an approach which juries always find extremely attractive – there is a real clarity of thought in the way she presents her case.’

Legal 500 2023 Leading Silk

Profile

Jo qualified as a solicitor in 1996. She worked for the Serious Fraud Office and the Crown Prosecution Service (CPS), latterly as a crown court advocate. She was called to the Bar in 2005 and has practised at Devon Chambers since then.

She was appointed King’s Counsel in 2018. She was the first barrister practising solely from chambers in Plymouth to be made silk and is the first female silk in Plymouth.

Since taking silk, Jo has built upon the substantial practice in heavyweight crime that she enjoyed as a junior and has cemented her reputation as one of the most sought-after barristers on the Western Circuit. She is regularly instructed by both the prosecution and the defence in crimes of the utmost gravity. She has a particular specialism in child cruelty and child fatality cases, and cases involving complex medical issues. She is well known for the care with which she handles cases involving young and vulnerable witnesses and defendants.

Jo also acts in family cases where there are complex fact finds involving either sexual allegations or allegations involving significant harm or death to a child.

In addition, as a junior barrister, Jo was recognised as an expert in fraud, confiscation, and cases under the Proceeds of Crime Act. Her work in this field ranged from advising the prosecution pre-charge to representing appellants before the Supreme Court. She maintains a strong interest in this area of the law.

Meticulous in her preparation and knowledge of the law, Jo understands above all the importance of instilling confidence in her clients. She is well regarded for the ability that she has to convey complicated issues in a ‘jury-friendly’ manner.

Jo is currently Leader of the Western Circuit – a position she will hold from 2022 to 2025. Jo is a senior trainer for the pupillage courses for the Western Circuit. She has also trained police officers, CPS advocates and local authority lawyers on confiscation and money laundering issues. She was a founder member of the Western Circuit Women’s Forum and acts as a mentor to junior female barristers. She undertakes pro bono work on behalf of Advocate.

Jo is authorised to undertake work in accordance with the Public Access Scheme, which means that members of the public can instruct Jo directly.

Jo is regulated by the Bar Standards Board.

Jo sits as a Recorder in both crime and private law family matters.

Recent Cases

R-v-D (2024). Leading Piers Norsworthy. Prosecution of man who had killed a stranger in the park. Lengthy psychiatric evidence dealing with diminished responsibility.
R-v-H (2023). Leading Jason Beal. Defence of woman jointly charged with new partner for the murder of her toddler. Complex medical evidence including forensic odontology.
R-v-B (2023). Prosecution of man for the murder of his ‘drinking buddy’. Causation of death a significant issue.
R-v-R (2022). Leading Patrick Mason, Albion. Defence of man charged with the double murder of his neighbours. High profile case. Issues of diminished and PTSD.
R-v-R (2021). Leading Mark Worsley, Guildhall, Prosecution of man charged with murder of an elderly woman who he was employed to care for.
R-v-B (2021). Defending a young man charged with rape. Original trial conviction overturned on appeal.
R v C (2021). Leading Jodie Mittel 3PB. Defending a woman charged with killing her baby. Complex medical issues particularly in relation to timing of the injuries.
R v B (2020). Leading Jane Rowley 3PB. Defending a man charged with murder by ‘strangulation’ of a woman with whom he had had an affair for many years. High profile prosecution with considerable press interest. Involved analysis of forensic evidence and tactical decisions on defences and plea.
R v G (2020). Prosecution: Baby died in a bath having been left by the defendant for some minutes. Defendant charged with gross negligence manslaughter and child cruelty in the alternative.
R v V and W (2018). Leading Sally Daulton for the prosecution. Both parents prosecuted in relation to life changing injuries to their 4 month old baby. Charges included s18 GBH and a joint charge of failing to protect the baby. The presentation of the case required detailed analysis of phone records and timings of various injuries to enable the jury to decide which parent had caused the significant injuries. There were connected family court proceedings.      

R v M and others (Operation Fardel). (2017-2018). Leading Julia Cox. Instructed by CPS South West Complex Casework unit – prosecuting six defendants for laundering in the region of £2 million through ‘harvested’ bank accounts and through the Post Office. The underlying crime was ‘phishing fraud’: fraudsters got victims to transfer their savings by pretending they were calling from the bank. All six defendants pleaded guilty after the case was fully opened to the jury. Following a contested hearing, confiscation orders in the sum of £1.5 million were made.

Reported Cases

R-v-Harvey (Jack Frederick) Supreme Court [2015] UKSC 73; Court of Appeal: [2013] EWCA Crim 1104 (defending from the Crown Court to the Supreme Court). The point ultimately dealt with by the Supreme Court was whether VAT that had been paid, or accounted for, to HMRC should be included (as the Crown contended) in the gross turnover figure of a company when assessing the level of confiscation to be paid. The Supreme Court held (in favour of the defence) that the VAT should be excluded.
R-v-Burridge [2010] EWCA Crim 2847 – prosecution junior in response to 4 day appeal against conviction. The defendant had been convicted of the murder of his baby who had the classic triad of injuries and rib fractures of different ages. The issue on appeal revolved around ‘fresh evidence’ relating to the age of the rib fractures. The court ultimately concluded that the conviction for murder was unsafe and substituted a conviction for manslaughter.
R-v- Beresford [2020] EWCA Crim 1674 – defence appeal against conviction on basis of unreasonable intervention by trial judge. Court concluded that the judge’s involvement in the trial led to an unfair trial and ordered a re-trial.
R-v- Brehmer [2021] EWCA Crim 390 – defending.  An unusual case in which the defendant had been tried for murder, but convicted of manslaughter and the prosecution sought to appeal the sentence as unduly lenient and the defence appealed on the basis that the sentence was manifestly excessive. The trial judge had determined a basis for sentence (loss of control), however the defence considered the basis upon which the jury had convicted was unlawful act. The Court of Appeal determined the judge had been entitled to sentence as he did, but decided the sentence had been too lenient and increased the sentence.
R-v-Reeves [2023] EWCA Crim 384 – defending. The Court of Appeal agreed the judge had erred in his balancing of aggravating and mitigating factors and reduced the sentence as being manifestly excessive.