It is declared that the public policy of this state and the general purposes of the provisions of this title are:
1. To proscribe conduct that unjustifiably and inexcusably causes or threatens substantial harm to individual or public interests;
2. To give fair warning of the nature of the conduct proscribed and of the sentences authorized upon conviction;
3. To define the act or omission and the accompanying mental state which constitute each offense and limit the condemnation of conduct as criminal when it does not fall within the purposes set forth;
4. To differentiate on reasonable grounds between serious and minor offenses and to prescribe proportionate penalties for each;
5. To insure the public safety by preventing the commission of offenses through the deterrent influence of the sentences authorized;
6. To impose just and deserved punishment on those whose conduct threatens the public peace; and
7. To promote truth and accountability in sentencing.