Alderney's President tipped the balance in favour of banning smoking in public places at Wednesday's States meeting.
The island's ten politicians were split over whether to introduce anti-smoking legislation before Sir Norman Browse, a former surgeon, stepped in.
The President, who is not obliged to vote when the States is divided, said: "I have voted because I think voting for [a ban] does more good for the whole island in every conceivable way.
"I hope I have made the right decision - we will know in future."
Earlier in the evening Richard Willmott made an impassioned speech in favour of introducing the ban, which will outlaw smoking in pubs and see the island follow in the footsteps of Guernsey and the UK.
Mr Willmott said: "Nobody doubts the need for clean water, so what about clean air?
"For us to gain a reputation as Britain's only smoking island would be very sad indeed."
Mr Willmott also said the legislation would improve the health of islanders, protect workers, encourage smokers to quit and have tourism benefits.
Boyd Kelly supported Mr Willmott.
He said: "It is hardly a secret that smoking kills. Eighteen years ago I woke up in intensive care with a smoking-related illness that nearly killed me."
John Beaman led the anti-ban members. He said the legislation was unnecessary and would lead to pub closures.
"We should concentrate our efforts on educating young people about the dangers of smoking. A ban will only damage the licence trade. We do not have to copy Guernsey and the UK."
Tony Llewellyn agreed with Mr Beaman. He said persuasion, rather than compulsion, was key.
"The solution is education, education, education; not regulation, regulation, regulation."
Several amendments, including one to only enforce a ban between April and September, were rejected during the debate, which lasted for more than two hours.
In the end, Mr Willmott, Mr Kelly, Bill Walden, Liz Bennett and Colin Williams backed the ban, while Mr Beaman, Mr Llewellyn, Peter Allen, Geoffrey Sargent and Ian Tugby voted against. The ban will come into force at 4am on June 1.
Meanwhile, the States also picked this year'??s committee chairmen. Mr Willmott and Mr Walden will remain as chairmen of Policy and Finance and General Services respectively. Geoffrey Sargent was elected as chairman of Building and Development Control after Liz Bennett stood down from the role.
The Guernsey Bereavement Service has made three visits to Alderney over the past few months and would like to continue to help you. We are visiting the island again on
Tuesday, 12th November 2013 and would invite anyone who feels they would like Bereavement Counselling to telephone the Bereavement Service Office on 257778 to make a time to meet one of our counsellors.