REDDITCH MP Karen Lumley voted against a proposal to ban smoking in cars and England and Wales when children are present.
But despite some opposition, MPs voted in support of the ban, following a vote on Monday, February 10.
The Labour-supported amendment to the Children and Families Bill passed by 376 votes to 107, and gives the government the power to bring in a ban if they wish to - but does not mean an immediate change in law.
The proposed ban was put to Parliament by the Labour Party, and endorsed by the House of Lords.
It came before Parliament follows a campaign by Public Health England to ensure parents fully understand the dangers of second-hand smoke and are encouraged to stop smoking in the home or car if there is a child present.
Evaluation of those campaigns shows they are increasing awareness of the risks of second-hand smoke as well as changing attitudes and behaviours.
Speaking before the vote, Mrs Lumley said: "Second-hand smoke is dangerous for children and it is right that we look at it as an issue. I will be listening with interest to the views expressed in the debate but do not believe that this is an issue that can or should be legislated for.
"Attitudes must and are changing but in my opinion the power of the state should not be advanced further into unnecessary private matters such as these. I am a strong believer in personal responsibility and certainly would not support the possibility of ordinary people being criminalised in this way.
"Furthermore, a ban would be wholly unworkable and impossible to enforce, creating great difficulties for the already stretched police. ”