Commissioned by the Ministry of Justice, the Palais de Justice will play host to Lille's high and district courts.
It will be situated west of the city centre, a short distance from a historic fortress. Built in 1667 by the French military engineer Sébastien Le Prestre de Vauban, the fortress has a star-shaped arrangement.
Rotterdam-based OMA decided to mimic this in its design, hoping to "address a wide range of different elements from the city's past and present".
The courthouse will have a pointy, hexagonal form, with each facade completed in a different coloured glass.
A triangular tower will extend up from its centre, accommodating a series of small courtrooms, and will be enclosed by a ring of offices that sit above the building's base. This base level will also play host to larger courtrooms.
Internally the building will be completed with light-hued flooring and furnishings, intended to create a more welcoming environment.
"The interiors of each of the building's components are conceived to make all the procedures of justice accessible, even inviting, free of the intimidation that has traditionally been the main characteristic of the architecture of justice," said the firm in a statement.
The design was selected ahead of shortlisted proposals by French practices Coldefy & Associés with Japanese architect Sou Fujimoto, Dominique Perrault Architecture and Dutch firm Neutelings en Riedijk.
The courthouse is scheduled for completion in 2023. It will be OMA's first project in Lille for over 20 years, coming after its design of the city's Congrexpo conference and exhibition centre in 1994.
The practice, whose design team is led by Rem Koolhaas and Ellen van Loon, has most recently erected a trio of residential towers in Miami and restructured a government office building in The Hague.
Renders are by ArtefactoryLab unless stated otherwise.