The Boston City Council adopted a proposal by Mayor Kevin H. White last night to stiffen the fines for hitchhickers and motorists who pick them up.

Anti-hitchhiking ordinances were drafted by Boston and Cambridge last week in the aftermath of the killing of an Emerson College coed, who may have been murdered while hitchhiking to class.

White's bill imposes a $5 fine on hitchhikers and a $25 fine on motorists who pick up hitchhikers. White vetoed a bill in December 1969 that would slap motorists and thumbers with $50 fines.

Cambridge Ordinance

Cambridge Councilman Walter Sullivan proposal to raise hitchhiking fines to $25 in Cambridge.

At present, the only Cambridge ordinance that penalizes hitchhikers is a jaywalking law, which prohibits standing in a roadway to solicit a ride. The current fine is $1 for the first, second, and third offenses, and $2 for the fourth offense in a year.

George Teso, director of Traffic and Parking in Cambridge, said yesterday that the fines are rarely enforced. "Hitchhiking regulations are governed by a state statute, and we can't change the rule, except by increasing the fine," he said.

A e gean at the Cambridge police station said yesterday that the present hitchhiking how is not worth enforcing.