It’s quite normal in the 20th century for criminals to impersonate another person for self-gain. For instance, there have been stories of bank robbers dressing up as bank managers in order to steal money.
In 1888, a man introduced himself as Father McCarthy of Montreal to a head priest in Washington, D.C. Later that day, McCarthy went down to the local jewelry store to look for a gift for the cardinal. He asked one merchant to bring a few diamonds over to the chapel where he was staying.
When the merchant arrived with the goods, McCarthy asked if he could take the diamonds to another room to show other holy men. Instead, he slipped out the back door, never to be seen again.