Factual error: When Diane visits her father in prison, she hands him a pen, but visitors in prison are very closely searched - no way could a visitor give a prisoner a pen of any kind (they're contraband for prisoners as they can be used as weapons), let alone a heavy pen like that one. Even if he were in a minimum-security prison (which his orange jumpsuit seems to indicate he's not) this rule would still apply.
Trivia: The Smithereens were commissioned by Cameron Crowe to write the theme song for the movie, and they came up with "A Girl Like You." Crowe thought that the lyrics were too leading (they outline the entire plot), so he rejected it in favor of Peter Gabriel's "In Your Eyes." "A Girl Like You" went on to be included in the Smithereen's next album, "11."