Can a person have two different handwritings?

I am watching a show on Discovery Channel called True CSI where they are hearing suspects of a murder.
The suspects are ordered to give a sample of their handwriting (after the woman was killed, the murderer, apart from stealing stuff from her house, also tried to do credit card fraud, hence the handwriting sample).
My question: is it possible for a person to develop a second handwriting (the one totally different from the other), to avoid, in a case like this, being caught?