Police deny that they didn't seek an opinion from Crown Law on the John Banks case because they didn't have enough resources.
Crown Law was not consulted before police decided that there was insufficient evidence to prosecute the ACT MP for knowingly filing a false electoral return relating to his failed bid for the Auckland mayoralty in 2010.
The prosecution was taken up by private prosecutor Graham McCready and then by Crown Law.
Mr Banks was found guilty by a judge last week and will resign as the MP for Epsom at Parliament on Friday.
Assistant Police Commissioner Malcolm Burgess said on Wednesday that police consulted an in-house lawyer on the issue and the decision had nothing to do with resourcing issues.