a slovak, from 1985 he worked as the head of a legislative department of the czechoslovak federal government. in april 1988, he became a minister - the chairman of the legislative committee. during the velvet revolution, on 10 december 1989, he was appointed prime minister in place of discredited ladislav adamec. although he himself was a member of the ksč, this government had a non-communist majority. he thus headed the first cabinet in 41 years that was not dominated by the ksč. when president gustáv husák resigned from his office shortly after swearing in the government, čalfa also took on most presidential duties until the election of václav havel on 29 december.