BALTIMORE CITY, MD — A cabal of corrupt corrections officers and members of the Black Guerilla Family gang enjoyed nearly free rein inside the Baltimore City Detention Center, federal authorities allege, smuggling drugs and cellphones into the jail and having sexual relationships that left four guards pregnant. An indictment unsealed Tuesday names 25 people — including 13 women working as corrections officers — who face racketeering, drug and money laundering charges. It alleges that Tavon White, an inmate known as “Bulldog,” took control of the prison gang soon after his arrival in 2009 on an attempted murder charge.