During his 31-year regime, dictator Rafael Trujillo appointed four individuals to serve as ceremonial presidents while retaining direct, behind-the-scenes control of the executive branch.

He was appointed minister for justice (attorney general) and public education by President Ramón Báez in 1914 and retained that position in Juan Isidro Jimenez's government.

His brother, Francisco, had negotiated with Charles Evans Hughes the treaty that terminated the occupation by the United States Marines in 1924.

Peynado served as secretary of the interior, police, and war in General Trujillo's subsequent government.

Peynado married María de las Mercedes Soler Machado (1880–1956) on February 14, 1900.