Crown Counsel are lawyers, generally in Common Law jurisdictions, who provide advice to the government and acts as prosecutors in cases. In various jurisdictions their title can vary and they could also be known as the Queen's Advocate, King's Advocate or Crown Advocate.
In some Canadian provinces they are titled Crown attorney.
In Hong Kong, following the handover of Hong Kong to China, Crown Counsel were re-titled Government Counsel.
References
Crown Counsel Wikipedia(Text) CC BY-SA