With regard to procurement legislation, it it legally permissible for purchasers to use random methods in order to shortlist suppliers?

This issue is governed by European Commission Regulations 26 and 27. Regulation 26 states that suppliers must be rejected who have been found guilty of serious fiscal crimes. Regulation 27 indicates that selection criteria must be based on “objective criteria and rules”. Other than this, there is no legal guidance regarding what criteria must be used.