Judges in London are hearing appeals from 10 individuals jailed for involvement in the rioting and looting that hit Britain in August.
The defendants are arguing against what they deem "excessive" sentences. They include two men sentenced to four years in prison for setting up Facebook pages inciting others to riot.
More than 1,700 people have been charged and nearly 200 jailed for offenses connected to the riots that started in London and spread to several other English cities.
Three judges at London's Court of Appeal will hear the cases Tuesday and decide whether the sentences handed down were proportionate to the crime.
The judges are not expected to rule until a later date.