Songfacts®:

• This song is about a compulsive liar. Aimee Mann explained to Billboard magazine: "I wrote 'Lies of Summer' about somebody who's had a specific kind of crisis, and all their lies and craziness exposed. I think once you realize that somebody's a pathological liar, then you kind of scroll back through all the encounters that have just been slightly off, and then you see those in a different light."
• This is one of several songs on Mental Illness about crazy, dysfunctional people – hence the album title. Mann explained to Elle:
  
  "I told a friend that I was working on a record and they said, 'What is it about?' And I said, 'Oh, you know, my usual songs about mental illness.' They said, 'Oh, you should call it Mental Illness,' being a smartass. Then I thought, Wait a minute, that's kind of great. Because it's so ridiculous, but it's also accurate, so it really did make me laugh."