Here's an interesting Washington Post article about a murder defendant who, by writing jailhouse letters, implicated himself in the crime, invited his girlfriend to perjure herself, solicited others to intimidate and/or murder witnesses in his trial, and butchered the English language and grammar.
While the first few things are just stupid, the last probably actually reflects his real speech patterns. He spelled Murder "murda", with "wit" and they "dae." His handwriting is actually quite readable, too!
