To my knowledge EMD is not a law and/or required, but it is customary and common. There is a spot for it on the purchase contract. Sellers like to see an EMD as it shows the buyers interest and readiness to buy.
This is simply my opinion and not to be taken as legal advise as I am not an attorney. I would suggest that you contact a Real Estate Attorney for all the legal details.
If I can be of any further assistance please feel free to contact me.
Have a Happy New Year!
Anthony Alleva, CSSA
Certified Short Sale Agent
Allison James Estates & Homes
Cell: (757) 768-9412
Fax: (800) 215-0211