Originally Posted by
May90
Actually, pretty much everyone in Mass Effect universe has a translator (for example, in one of the conversations with Thane, Shepard says, "I think my translator just glitched. What did you call me?"). Also, I believe, at the time of Mass Effect 1 events, humans were relatively rare in C-Sec, they become the main force there after the Sovereign attack, when a lot of C-Sec officers died in the fighting and humans were the most eager to replace them.
As for Mordin, I didn't know this about him. When does he mention it?