CCTV caught the horrific gangland-style “hit” on Vicente Antonio Bermúdez Zacarías yards from his gated community in Metepec, Mexico.
Two men can be seen running behind Mr Zacarías – dressed all in black – before one shoots the judge in the head.
The pair then flee the scene in a car.
The 37-year-old judge was taken to hospital but died from his injuries at around 8.30am.
Many know him for having ruled on the some of Mexico”s biggest drug lords.
Police have so far refused to comment on suggestions the murder of Mr Zacarías is linked to narcos.
Mexican président Enrique Pena Nieto has ordered his attorney general to investigate the murder.
Mr Zacarias recently suspended the extradition of Joaquin “El Chapo” Guzman to the US to face drug trafficking charges.
But he approved the extradition of Abigail Gonzalez Valencia – leader of another cartel known as “Los Cuinis”.
He reportedly offered soldiers a $3million (£2.4m) bribe to not have his face shown on TV – but his offer was refused.
It comes after shocking footage emerged of El Chapo”s son being kidnapped in a packed restaurant.
Jesus Alfredo Guzman Salazar, 29, can be seen on his knees with a machine gun to his head after seven attackers burst into the exclusive restaurant.
In July it was rumoured El Chapo had managed to break out of his cell for a third time – but the rumours turned out to be false.