The recent UK Government cabinet reshuffle is further proof why Wales should have its own criminal justice system, Plaid Cymru's Westminster leader has said.
MP Elfyn Llwyd used his address to the Welsh nationalist's conference to renew calls for further devolution.
The 60-year-old insisted justice in Wales would neither be fair nor robust until responsibility over the matter lies in the hands of Welsh people.
Mr Llwyd said: "The appointment of Chris Grayling as Secretary of State for Justice, for example, only strengthens the need for criminal justice to be devolved to the Welsh Government.
"I'm afraid Grayling will speed up the privatisation of the prison estate and youth justice - a catastrophe waiting to happen, if the mess that surrounded G4S before the Olympics was anything to go by.
"There will be those who oppose further devolution, who continue to argue for the status quo, those who are nervous of more change. But we know that it is only through obtaining these powers that we can tackle the problems facing our communities firsthand, and structure our services so that we administer to the people who need them most."
Last year, a referendum saw Wales gain primary law making powers in 20 devolved areas.
Despite disquiet from campaigners who urged the electorate to vote No in that poll, politicians have since been debating whether the principality should have control over matters like taxation and broadcasting. The matter of further powers has been examined by the independent Silk Commission - and a public consultation about Wales having a separate legal jurisdiction was undertaken earlier this year.
Mr Llwyd told delegates at conference venue Theatr Brycheiniog in Brecon: "In a sense, Wales already has its own jurisdiction, since laws passed by the Assembly pertain only to Wales. Lawyers who practice environmental, criminal, family and administrative law must have a thorough knowledge of the corpus of Welsh law if they are to practice in Wales.
"Although criminal law has yet to be devolved, any new Act passed by the Assembly may contain a new or amended criminal offence. A separate courts structure to support this budding jurisdiction would undoubtedly facilitate the process."