The growth in England and Britain's merchant marine from the medieval period onwards meant that an increasing number of criminal offences were committed on or against the country's vessels while they were at sea. Between 1536 and 1834, such crimes were determined at the Admiralty Sessions if brought to trial. This was a special part of the wider Admiralty Court, which, unlike the other forums in that tribunal, used English common law procedure rather than Roman civil law to try its cases. To a modest extent, this produced a 'hybrid' court, dominated by the common law but influenced by aspects.