The government also closed down two local newspapers, 14 associations and one health clinic, according to the Gazette.
Thousands of people have fled Turkey due to a massive witch-hunt launched by the Justice and Development Party (AK Party) government against sympathizers of the Gülen movement in the wake of a failed coup attempt on July 15.
Fetullah Terrorist Organization (FETO) - the group behind last year's defeated coup in Turkey - is led by Fetullah Gulen, who has been living in a self-imposed exile in the United States since 1999.
Gulen, who has lived in self-imposed exile in Pennsylvania since 1999, denies any links to terrorism and the failed putsch.
Ankara also accuses Gulen and his followers of infiltrating state institutions.More news: Orrin Hatch grateful for 'honor' from Utah newspaper criticizing him
The decree also reinstated 115 people in public sector jobs who were previously dismissed. But critics say the government crackdown is just an excuse to silence political opposition as well as journalists and members from the Kurdish minority.
According to the decree, female suspects and convicts are exempt from wearing the uniform.
The decision comes months after a defendant accused of links to the coup wore a T-shirt with the word "hero" emblazoned on it, sparking a public outcry. Male defendants will now be required to wear "almond and gray-colored uniforms".
Erdogan previously said that alleged coup-plotters would wear clothing similar to the notorious orange jumpsuits used at the United States military prison in Guantanamo Bay.
"They won't be able to appear in court with a tie, in an ostentatious way", he said.