A dress code could require wearing a gun (i. e. wearing both a gun and a holster - when someone puts a vest on you say they're wearing a vest even if the vest only touches the shirt - ditto shoes and long socks) and nothing else and it would still be a dress code. I would even say that a policy that you can wear anything is a dress code in the same way the unlicense is a license.
I think that undercover or plainclothes in most cases has enough rules that it constitutes a dress code, even if you think a dress code needs to have rules about more than one article of clothing to be considered a dress code.
Afaik, mafia does not require gun and holster on you typically. Plus, in situation where you have to have one, it is closer to requirement to have a tool with you then dress code.
I don't understand why the need to twist mafia into dress code group. Russian mafia is know entity, so is albanian one. Ukraine mafia exists too. It is just that, dress code is not what would be associated with them.
Point taken. I retract my statements. I think it is possible to have a dress code for under cover policing. I guess the only thing left is that I think that a dress code is not the same as a uniform, and that an undercover operation could have a dress code similar to a nightclub, where there are rules but no specific products that have to be worn.