The CRC further requires that the treatment takes into account the child's age and promotes the child's reintegration into society. Professionals involved in the juvenile justice system must therefore be “knowledgeable about child development, the dynamic and continuing growth of children, what is appropriate to their well-being, and the pervasive forms of violence against children.”23 2.7. MINIMUM AGE OF CRIMINAL RESPONSIBILITY Article 17 of the ACRWC categorically provides that “there shall be a minimum age below which children shall be presumed not to have the capacity to infringe the penal law.” 24 The Committee on the Rights of the Child (the Committee) has argued that a minimum age of criminal responsibility below the age of 12 years is not internationally acceptable and recommended that States Parties increase the age to 12 years as the absolute minimum25.The UN General Assembly has also argued that “if the age of criminal responsibility is fixed too low or if there is no lower age limit at all, the notion of responsibility would become meaningless.”26 2.8. GUARANTEES FOR A FAIR TRIAL Both the CRC and the ACRWC contain guarantees that are meant to ensure that a child in contact with the law receives a fair treatment and trial.27 These guarantees are minimum standards. 2.8.1. No retroactive juvenile justice Article 40(2)(a) of the CRC provides that no child should be charged with or sentenced under the penal law for acts or omissions which at the time they were committed were not prohibited by national or international law.28 International law also prohibits the imposition of a heavier penalty than the one that was applicable at the time when the criminal offence was committed. A child should however benefit from a change of law providing a lighter sentence than the one that was applicable at the time of the offence.29 2.8.2. The presumption of innocence Both the ACRWC and the CRC provides that a child accused of having committed an offence shall have a right to be presumed innocent until proven guilty.30The prosecution bears the onus to prove the charge against the child beyond reasonable doubt. All public authorities or others involved in the juvenile justice must refrain from prejudging the outcome of the trial. 2.8.3. The right to effective participation in the proceedings A fair trial requires that a child effectively participate in the trial. The proceedings should be conducive to the best interests of the juvenile and conducted in an atmosphere of understanding which allows the juvenile to participate therein and to express himself freely.31 It is crucial to consider the child's age, maturity and other special needs in dealing with effective child participation hence courtroom procedures and practices may have to be modified in dealing with children. 23 ibid p4 See also Article 40 (3) of the CRC 25 General Comment No. 10 (2007) op cit p8-9 26 The Beijing Rules op cit Rule 4 27 Most of the guarantees are also contained in Article 14 of the ICCPR. 28 See Article 15 of the ICCPR 29 See Article 15(1) of the ICCPR 30 Article 17(2)©(i) of the ACRWC and Article 40(2)(b)(i) of the CRC 31 The Beijing Rules op cit Rule 14.2 24 11