The International Criminal Court (ICC) in The Hague investigates and, where justified, brings to justice persons indicted for the most serious crimes of concern to the international community: genocide, war crimes, crimes against humanity and the crime of aggression. 5 years after graduating from the Delft University of Technology Gemma Koppen, commissioned by the Dutch Governmental Building Agency, takes up the challenge to design the ICC. Taking into consideration the high security requirements and visibility of the Court, the client (ICC taskforce) focused on four main issues. Cost, rapidity of construction, accessibility requirements and the fact that the building was temporary in nature. Access is required at the same time for judges and staff members, the accused, victims, as well as for media representatives and the general public. During an initial feasibility study, various options were explored, regarding where to construct the Courtroom; at that time the Court occupied only one wing of the entire existing building. From three final proposals presented, the option to use the garage was chosen as it was the easiest area to access from the existing building as well as the street. In order to fulfil the security requirements for those entering the new wing, Gemma Koppen designed the building to incorporate various separate entry routes, using colors to visually differentiate them from one another. Earthy colors are used for the accused, primary colors for security and staff members, birch for the Judges representing the calm, serious nature of their work. Blue in the public and media areas, according to numerous studies, representing justice, confidence and intelligence. The height of the garage decks left her with a major challenge. Public buildings are not generally built to heights as low as 2.25 meters. By placing all installations, including lighting at floor or wall level, the appearance of height and openness was maximized.
Three huge holes surrounded by glass were cut in the floor of the media center, giving visitors using the briefing room below the feeling of increased space and light. Acoustic materials have been used in the walls and ceiling in these areas. She decided not to hide the fact that a garage was the basis of the structure, on the contrary, the contrasting elements of the old building against the new temporary features are a major feature of her design. The weight of the proposed Courtroom and public facilities was a concern. Too great for the current supports of the garage, it was necessary to insert concrete – filled steel pillars which pierce through the existing floors, with their own foundations, so as not to have to reinforce the existing floor. These are visible throughout the new structure, giving the feeling of continuity between the different floors, while contrasting against the original concrete car park pillars. Gemma Koppen took on board the orderly and regimented nature of the Court as a legal institution and decided that the construction would be just the opposite. Windows and lighting are positioned in an irregular manner. The outside of the building has been designed so as not to compete with the existing structure but to subtly stand out from it. A glass skirt around the bottom of the structure gives it the feeling of floating above the ground, making the structure appear much lighter; it is lit up at night. The design is calm but at the same time strong. The metal curtain that winds around the building is composed of two elements, flat and convex lines were chosen to stop it appearing barn-like. Spaced out with three flat-shaped followed by three convex-shaped bars, play of light is created. What is in fact two-tone, gives the impression of four colors making the building very distinctive from the road. The building has become the backdrop for impressive cinema and TV productions on the international defence of human rights.