The offences of slaves were punished with severity and frequently the utmost barbarity. Terrible punishments were devised where slaves were crushed to death or had their hands, ears, feet, nose and lips cut off and their eyes cut out. However, some slaves were expensive commodities, especially those who were highly skilled or educated, so punishments for this type of slave were often less severe.

Roman Attitudes to Slave Punishment
Under the Roman Republic the owners of slaves were allowed to inflict whatever treatment or punishment they wanted on a slave. The Latin word Potestas was  applied to the master's power over the slave, and the same word was used to express the father's power over his children. No injury or punishment inflicted by an owner was a crime. It was not illegal to kill a mere slave - they were not perceived as people they were perceived as commodities. When property or goods were sold which included slaves there were no rules preventing the splitting of husband and wife, parents and children, brothers and sisters. These Roman Laws did eventually change during the later era of the Roman Empire.

Slave Punishment - Death by Crucifixion
When punished for any capital offence, they were commonly crucified (although this was eventually prohibited under the rule of the Emperor Constantine). Roman law would crucify a slave for almost any reason, such as stealing. The slave was first scourged and then stripped of his clothes and nailed or bound to the cross. The nails were inserted just above the wrist, between the two bones of the forearm or driven through the wrist. When nailed to the cross there was a massive strain put on the wrists, arms and shoulders often resulting in a dislocation of the shoulder and elbow joints. The slave was unable to breath and eventually died from asphyxiation. Crucifixion meant a painful and lingering death. The length of time required to die from crucifixion could range from hours to a number of days. Instances are recorded of persons who survived nine days during the process of death by crucifixion. 

Slave Punishment - City slave sent to the country
A slave punishment was to be removed from the familia urbana (city) to the rustica (country). Country-slaves were treated more cruelly than city slaves. Country slaves worked in chains and were kept in a guarded work-house (ergastulum) at night. Some of them were branded or had tattoos engraved on their forehead. Some country slaves had their heads shaven and their hair was used to produce wigs for wealthy Roman women. It was therefore a severe punishment for a town-slave to be sent into the country.

Slave Punishment for Killing the Master
At its peak during the Roman Empire it is estimated that slaves outnumbered citizens 5 to 3. It is therefore not surprising that Romans were terrified of slave uprisings or rebellions. Many slaves must have been driven to assaulting or murdering their owner but were stopped by the slave punishment for killing the master of the house. The slave punishment for assaulting the master of the house, or members of the family, was therefore swift and severe. The punishment was to torture and kill all slave members of a familia when one had assaulted an owner.

Slave Punishment - Runaway Slaves
A runaway slave could not legally be the object of sale. A class of persons called Fugitivarii made it their business to recover runaway slaves. The rights of the master over the slave were in no way affected by his running away. Runaway slaves were branded on the forehead with letters denoting the slave as a runaway (FUG) which was an abbreviation of "fugitivus," meaning "runaway". The deliberate breaking of the joints or bones was also a punishment inflicted on runaway slaves.

Slave Punishment - Branding or Tattoos
The slave punishment for theft was to be branded on the forehead with the letters "FUR", from the Latin word for thief which was "fure". Tattooing was sometimes used instead of branding as a means of permanently marking a slave with the sign of his crime.  New slave recruits to gladiator schools had Roman tattoos (stigma, from where the English word stigmatised derives) applied as an identifying mark on the face, legs and hands.