Historically, the primary method of treating offenders has been custodial sentencing. Arguments for custodial sentences are that dangerous offenders cannot harm members of the public whilst detained and the realities of a prison lifestyle will dissuade offenders from future behaviour that could produce a custodial sentence. However, more recent studies have suggested that with regard to reducing re offending rates custodial sentences have had a limited effect; Lambie and Randall (2013) found that 70-80% of juvenile offenders in the US re offend within three years of the end of their custodial sentence. The authors suggest that interruption of the maturation process by removal and alienation from friendship groups and social circles leads to an incomplete maturation that prevents the natural process of offending behaviour reducing as one grows older. Furthermore, prison often forces juveniles into contact with older, more experienced criminals to fit in. This can encourage juveniles to attempt more criminal acts as older and more experienced criminals become role model. Therefore, although custodial sentences prevent offenders from committing further crimes immediately in the long term it can lead to a higher chance of re offending. Another method for treatment of offenders if multi systemic therapy (MST). MST is a short term (4-6 months in length) programme with therapists working in the homes of families with problematic and antisocial behaviour. A therapist may help with issues such as discipline, family affection and school attendance for example. Curtis et al (2004) found that 70% of those that took part in an MST programme in the US felt better off for taking part and the Missouri delinquency project found that both those that completed and dropped out of a course of MST had lower re offending rates than those that completed intensive therapy courses. However, Littell et al (2005) cnducted a systematic review of MST and found no significant effect compared to out of home placements. However it could be argued that although the positive effect of MST compared to other methods is debatable it does not have the negative effect of a custodial sentence.