In 1839–40, the court was the location of the trial of the Chartist leader John Frost and others for high treason for their part in the Newport Rising.

It is currently used as a tourist information centre and as the offices for Monmouth Town Council, and parts are open to the public.

The timbers from the original building were used in the construction of the Shire Hall, which provided an open trading area on the ground floor with rooms above.

[5] It is generally thought to be of decidedly poor quality; John Newman considered it "incongruous",[3] Jo Darke called it "decidedly-bad",[6] while the local historian Keith Kissack attacked it in two separate books, describing it as, "rather deplorable",[2] and "pathetic...like a hypochondriac inspecting his thermometer".

It was here that the Chartist leader Henry Vincent, who had sought the right of all men to vote in parliamentary elections, was imprisoned before being tried at the assizes.

A Special Commission opened at Shire Hall on 10 December 1839, and an appointed Grand Jury considered what charges to bring against them.

The Grand Jury included Lord Granville Somerset, brother of the Duke of Beaufort; John Etherington Welch Rolls; Octavius Morgan; and four Members of Parliament, Joseph Bailey, William Addams Williams, Reginald James Blewitt, and Sir Benjamin Hall.

[10][11] Granville Somerset and Benjamin Hall spoke in Frost's defence,[10] and, in his summing up, Lord Chief Justice Tindal drew attention to the complete certainty needed for a conviction, suggesting his desire for an acquittal.

The building now contains a Tourist Information Centre and offices, it is open to the public seven days a week from 10am – 4pm from April to September and is closed on Sundays in winter.

[24] The interior of the building was remodelled in 1828, and a new exterior stair tower with a glazed lantern was added, enclosing a grandiose new staircase.

[1][3] The work was undertaken by Thomas Hopper and Edward Haycock Sr. who extended the Shire Hall building along Agincourt Street, creating room for a new staircase and larger courts.

[22] Its Cadw listing record describes it as an "exceptionally fine example of provincial Baroque architecture and one of the two finest secular buildings in Monmouth".

[22][c] Immediately in front of the Shire Hall stands a Statue of Charles Rolls, the locally born motoring and aviation pioneer to commemorate his life achievements, it was unveiled in 1911.

The Kings Head Hotel stands opposite, which dates from the mid-17th century and was reputedly visited by Charles I of England in 1645.