Purpose The purpose of this paper is to quantify the characteristics of dual-harm behaviour in prison in comparison with sole self-harm or assault behaviour in prison, with an analysis of the distinguishing features. Design/methodology/approach Official data on in-prison incidents, demographic and offending information were analysed for 326 prisoners in two prisons in England. Findings Proportions of up to 42 per cent of offenders who assault others in prison will also engage in self-harm and vice versa. Dual-harm prisoners will engage in a broader and greater frequency of prison incidents than either sole group; with dual-harm prisoners reflecting greater proportions of damage to property and fire-setting. There were no differences in their time in prison or presence of serious violent current conviction, however, an index offence of drug supply was less likely in the dual-harm group, with minor violence slightly more likely in longer sentence prisoners. There was no difference for the dual-harm prisoners whether the first incident was self-harm or violence, with mean duration from sole to dual harm of less than three months. Practical implications In-prison behaviour can assist in the identification of prisoners at dual risk of harm. Greater inclusion of in-prison behaviour and awareness of dual harm in research methodologies may assist in improving risk management. A wider use of joint risk assessment and single case management approach is suggested for prisoners with dual-harm profile. Originality/value This is the first study on dual-harm behaviour in UK prisons and to evaluate their wider prison behaviour and offending characteristics.

中文翻译：

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双重伤害：探究监狱中双重暴力和自我伤害行为的存在和特征

目的本文的目的是量化监狱中双重伤害行为与监狱中唯一的自我伤害或攻击行为的特征，并分析其区别特征。设计/方法/方法分析了英格兰两所监狱中326名囚犯的监狱内事件，人口统计和犯罪信息的官方数据。结果在监狱中殴打他人的罪犯中，多达42％的罪犯也会自残，反之亦然。与任何一个单一群体相比，双重伤害囚犯将更广泛，更频繁地发生监狱事件。具有双重伤害的囚犯反映出更大比例的财产损失和着火。他们在监狱服刑的时间或被严重暴力定罪的时间没有区别，但是，在双重伤害人群中，很少有将毒品供应指数化的罪行，而在服刑较长的囚犯中，轻微暴力的可能性稍高。无论是第一次伤害是自残还是暴力，双重伤害囚犯没有区别，从单一伤害到双重伤害的平均持续时间少于三个月。实际含义监狱行为可以帮助识别遭受双重伤害的囚犯。在研究方法中更多地包含监狱行为和对双重伤害的认识可能有助于改善风险管理。对于具有双重伤害特征的囚犯，建议广泛使用联合风险评估和单例管理方法。原创性/价值这是对英国监狱中双重伤害行为的第一项研究，旨在评估其更广泛的监狱行为和犯罪特征。