The PAP, which has remained in power since independence, is believed to rule in an authoritarian manner by some activists and opposition politicians who see the strict regulation of political and media activities by the government as an infringement on political rights. In response, Singapore has seen several significant political changes, such as the introduction of the Non-Constituency members of parliament in 1984 to allow up to three losing candidates from opposition parties to be appointed as MPs. Group Representation Constituencies (GRCs) were introduced in 1988 to create multi-seat electoral divisions, intended to ensure minority representation in parliament. Nominated members of parliament were introduced in 1990 to allow non-elected non-partisan MPs. The Constitution was amended in 1991 to provide for an Elected President who has veto power in the use of national reserves and appointments to public office.