Course taster

A novel use of an expert witness

There are also very novel areas where expert witnesses can provide testimony. In one particular case, a male defendant in his 50s was arrested for drink driving and was asked to give a urine sample when stopped by the police (Davies & Beech, 2017). He refused because he had paruresis (or 'shy bladder' syndrome, whereby one is unable to urinate on command or in front of others). Instead, he offered to give a blood test. However, the officers did not believe his claim of paruresis and so they charged him with preventing the course of justice. In court, a forensic psychologist was called in who was an expert in paruresis to explain the condition and determine if the defendant did indeed suffer from this. Citing research by Hammelstein and Soifer (2006), which found paruresis to be more than just a social phobia and was an actual condition/syndrome, and using the defendant's medical records, highlighted that the defendant did indeed suffer from paruresis.

In the following section we'll consider the role of expert witnesses in civil cases.

Experts in civil cases

While forensic psychologists may largely comment in criminal proceedings, there are certain civil cases in which they may also testify.

Stop and think

What is the difference between civil and criminal proceedings (we briefly covered this in Unit 1)?


Criminal proceedings require a more stringent judgement than civil proceedings based on proof beyond reasonable doubt, and the level of certainty that a judge/jury must have to make a determination is much greater (Ashworth & Kelly, 2021) – these proceedings can also sentence individuals to custodial sentences.

Civil proceedings instead rely on proof based on probability - that is, judgements are made based on facts that indicate one likelihood over another (Ashworth & Kelly, 2021 ). These cases also do not hold custodial sentencing and instead any damages are repaid monetarily, or in family matters it may be that one parent receives custody rights over a child. A notable case that was settled in civil proceedings is the OJ Simpson case (Britannica, 2023). After criminal proceedings, OJ Simpson was found not guilty of murdering his ex-wife, Nicole Simpson, and her friend, Ronald Goldman (beyond a reasonable doubt; expert testimony was also used in this case). However, in civil proceedings he was found likely to be responsible for their deaths (based on probability) and so had to pay restitution to the families.

Family proceedings are also common civil procedures where you may see forensic psychologists as expert witnesses, often to comment on child development and how this may be impacted by parenting, or to discuss cases of neglect, amongst other things (Davies & Beech, 2017). In some instances, these civil proceedings may later become criminal proceedings if maltreatment is found towards a child.

Now that we've been introduced to the idea and function of expert witnesses, in the following section we'll consider their duties and obligations.