BUFFALO, N.Y. (AP) — An advocate for the homeless says employees of a Buffalo-area foreclosure law firm who mocked clients at a Halloween party last year need a lesson in homelessness.Pictures from the Steven Baum law firm's 2010 Halloween party turned up recently in the New York Times. They show people dressed like they're homeless and a sign reading "Baum Estates" near part of the office decorated to resemble a row of foreclosed homes.The Baum law firm is one of the largest volume mortgage foreclosure firms in New York. It recently agreed to pay $2 million and change its practices after a government investigation.The law firm has apologized for the party. Still, the Western New York Homeless Alliance tells WGRZ-TV that employees should do volunteer work to educate themselves.