Oblivion : how to get into the imperial legion offices ?

The offices are in the imperial city prison district . There are two doors which can get you into the offices . Both of them are classed as very hard to unlock . I have tried so many times to open them but I can't . I do have spells which are meant to turn any lock into very easy , but they don't work on this door. There is somebody wandering around the offices dressed in golden lined armor . I forgot his name though . Do I have to talk to him to get a key ? And by the way , I need to get into the imperial city offices as part of a quest called : ' taking care of lex ' . Please help me, no Internet guides are any good , so please help :D