A member of the NP's reform wing, he was critical of P.W. Botha for being too timid in his constitutional reforms in the 1980s and was also critical of the state of emergency implemented by Botha. In the 1987 general election, he left the NP and ran as one of three independent candidates along with former ambassador to London Dennis Worrall and businesswoman Susan Lategan. He was the only one of the trio elected, probably because he was the only incumbent. He subsequently quarreled with Worrall and so the two formed two separate political parties after the election. In early 1989 these two new parties joined up with the veteran Progressive Federal Party to form the Democratic Party, which won a record number of seats for a liberal party in the September 1989 whites-only election. He subsequently became one of three co-leaders of the new party and retained his parliamentary seat in the 1989 general election by defeating former Ambassador to Canada Glenn Babb who was running for the NP. Malan remained in the DP's leadership until 1993.