Alleged Baby Mama's Lawyer Justin Bieber Spermed My Client His Threats Don't Scare Me

11/16/2011 2:44 PM PST

Mariah Yeater's Lawyer -- Justin Bieber Spermed My Client, His Threats Don't Scare Me

The new lawyer for Justin Bieber's alleged baby mama tells TMZ, he firmly believes his client's allegation ... that the singer knocked her up  ... and says he's currently negotiating the terms of a DNA test with JB's legal team.

TMZ broke the story ... Yeater dismissed her paternity suit against the Biebs last week and her lawyers ran for the hills -- but her new attorney Jeffrey Leving tells us, he's not backing down.

As for Bieber's threats that he'll sue Mariah and her lawyers, Leving tells us, it's just another example of a celebrity trying to push around the little guy -- in this case "a 20-year-old woman with no money and no job."

Leving claims Mariah dismissed her lawsuit to open the door for a private settlement -- but Bieber sources tell us, there have been NO settlement discussions whatsoever between the two camps ... though there may have been contact about the terms of a DNA test.