this is the real life situation .  It will  happen  sooner or later u like it or not .

let  say  someone  stole  1000000 BTC  from the exchanger and they   want  to make them   Clean .
All they  have to do is  to buy NIX  then  swap  it for some BTC later   and here u  are  with  clean  BITcoins .Very  nice indeed  .
I'm sure the police won't like that  .They will try to  contact NIX devs and ask them  where the money  gone to ( what wallet ) ..

and sure enough DEVS will  cooperate .

Now tell  me  how is this a  privacy  coin  ?