Statutory timelines, technical specifications of
police instruments, on - scene presence or absence of roadside screening devices, etc. may affect the lawfulness of the
investigation, the obligation to provide a breath sample, and the admissibility of any samples taken;
inadequate caution about the right to counsel or opportunity to exercise it might warrant exclusion of evidence; a full strip - search in a routine case might warrant a stay of proceedings even if the accused «blew over».