The article analyses resolutions and rulings issued in 2017 by the Criminal Chamber of the Supreme Court and resulting from adjudication of legal issues concerning substantive criminal law, executive penal law, misdemeanour law and fiscal penal law. The article discusses: the concept of “the object of a prohibited act”, which is one of the elements of an unsuccessful attempt to commit an offence (Article 13 § 2 CC); condition for ruling conditional release of a person sentenced to the penalty of deprivation of liberty from serving the remainder of the penalty (Article 77 § 1 CC); the significance of a conviction for a crime committed by a convict released from prison without supervision (Article 138 § 1(8) EPC) as a negative condition for ruling an aggregate penalty in the form of an aggregate sentence (Article 85 § 3 CC); interpretation of a punishable threat determined in Article 190 § 1 CC constituting one of the elements of the definition of a threat (Article 115 § 12 CC); performing a public function by a person employed in an independent public healthcare institution (Article 115 § 19 CC); liability for trafficking the so-called designer drugs (Article 165 § 1(2) CC); legal significance of breaks between periods in which a perpetrator persistently evades the duty to take care by not providing maintenance for the next of kin or other persons (Article 209 § 1 CC); in case of change in legislation, application of a more relevant statute to a perpetrator (Article 4 § 1 CC) in order to rule a conditional suspension of the execution of the penalty of deprivation of liberty in penal executive proceedings (Article 152 EPC); the misdemeanour of alcohol consumption in a public place (Article 431(1) of the Act of 26 October 1982 on upbringing in sobriety and prevention of alcoholism); technical regulations in the gambling sector vs fiscal penal liability for an offence under Article 107 § 1 FPC (Article 6(1) and Article 14(1) of the Act of 19 November 2009 on gambling (Dz.U. 2015, item 612)); the phrase “within the time limit for tax payment” (Article 28(4) of the Act of 26 July 1991 on personal income tax).