With the power to make and enforce the law, the position of Chief Justice is an extremely powerful one within Cybertronian society and as such its holder is denoted by a golden headpiece.
History
2005 IDW continuity
The longest serving Chief Justice was Tyrest who was elevated to the position by Optimus Prime after establishing the Tyrest Accord, a cross-faction treaty designed to prevent Transformer technology falling into the hands of other races. House of Ambus
However, stress eventually broke Tyrest, and he started to develop a killswitch that would kill everyone on Cybertron he deemed 'guilty', which included half the planet, including himself.
Tyrest was almost successful in this genocide but was thwarted at the last second by Starlock and Veritas Prime. This Calamitous Life
After this, Tyrest voluntarily stepped down, and for now, the post remains empty.