Pretending to be another person or business as entertainment or in order to deceive is impersonation. Non-parody impersonation is a violation of the TOS, specifically article 4 which states:4. You must not abuse, harass, threaten, impersonate or intimidate other Twitter users.The standard for defining parody is, "would a reasonable person be aware that it's a joke." An account may be guilty of impersonation if it confuses or misleads others—accounts with the clear INTENT to confuse or mislead will be permanently suspended.
Parody impersonation accounts are allowed to exist. The profile information on a parody account must make it obvious that the profile is fake, or it is subject to removal from Twitter.com. If it is not evident from viewing the profile that it is a joke, it is considered non-parody impersonation. Non-parody impersonation accounts may be permanently suspended for Terms of Service violations.
4. You must not abuse, harass, threaten, impersonate or intimidate other Twitter users.