The first judicial facility in Lerwick was a medieval tolbooth in Commercial Street which was completed in the 17th century. After becoming dilapidated, it was demolished and replaced by a new tolbooth, which was built by the local masons, Robert and James Forbes, and completed in around 1770. The new tolbooth was used as a prison as well as a sheriff courthouse: however, in 1836, the prison inspector reported on the poor conditions in which prisoners were held and, by the mid-19th century, the justices were also seeking better facilities.
