The Netherlands is a parliamentary democracy. This means that the government is subject to parliamentary scrutiny. The government consists of the King, the Prime Minister and the ministers. Parliament consists of an upper house – the Senate – and a lower house – the House of Representatives. The monarch is the head of state. The Constitution (Grondwet) lays down that the ministers and not the monarch are responsible for acts of government. The Netherlands has been a constitutional monarchy since 1848.