According to the "Terms and Conditions" page of the service, the CoinJoin feature in Ginger Wallet is not available to U.S. citizens.

Additionally, it is not possible to change the default coordinator, which sends all inputs of a CoinJoin transaction to a blockchain surveillance company.

"We have partnered with one of the world's leading blockchain analytics companies. When new coins attempt to enter our CoinJoin for the first time, we use their coin verifier service to ensure that every coin you mix with has a low risk score," states the project's website.