Though she had previously sponsored legislation in New York to combat sex trafficking, Assemblywoman Amy Paulin said she had not realized how big a role hotels and hotel workers could play in the fight until she met with two activists.

“They made me aware,” Ms. Paulin said of Anneke Lucas, a sex-trafficking victim, and the Rev. Adrian Dannhauser.

Ms. Lucas started an online petition in January calling for legislation mandating that hotels post clearly visible signs explaining what sex trafficking might look like, and that they train employees how to recognize victims and signs of trafficking. The petition has more than 54,000 signatures.

Possible indicators of sex trafficking include guests who book multiple rooms, rent rooms by the hour and pay cash, or men accompanied by young girls who appear downtrodden or do not make eye contact. Girls tattooed with “Daddy’s Girl,” “Daddy’s Little Money Maker” or bar codes are other potential signs, said Carol Smolenski, the executive director of Ecpat-USA, or End Child Prostitution, Child Pornography and Trafficking of Children for Sexual Purposes, a Brooklyn offshoot of the international group.