Ms Davidson worked as a journalist with the BBC and Real Radio
The Scottish Conservatives have chosen former BBC journalist Ruth Davidson as their candidate for the Glasgow North East by-election.
Ms Davidson called on candidates from other parties to "fight a clean and honest campaign".
The 30-year-old is the second former BBC journalist to stand. The SNP chose 35-year-old David Kerr.
The Glasgow North East by-election was sparked by the resignation of Commons speaker Michael Martin.
Following her confirmation as the Conservative candidate, Ms Davidson said she was "honoured" to have been chosen.
"I will begin by pledging to fight an honest campaign," she said.
"Since the controversy over MPs expenses people have lost trust in politics and as a result I think it is important to fight a campaign that engages people rather than turns them off politics.
"I may disagree with the other candidates on many issues from justice policies to the economy but that doesn't mean we shouldn't fight a clean and honest campaign.
"We should be focusing on what matters to people in Glasgow North East not on doing each other down by resorting to smears and fears."
'Top class' candidate
Conservative leader David Cameron said: "It is great that she has pledged to fight a clean and honest campaign.
"Politics is about winning arguments, not smears and fears. I look forward to coming to the constituency during the campaign and supporting Ruth's challenge."
Ms Davidson spent most of her nine years in journalism with BBC Scotland where she worked as a presenter, news journalist and documentary maker. She also worked for Real Radio.
She left the corporation earlier this year and is now studying international development at Glasgow University.
Scottish Conservative leader Annabel Goldie described Ms Davidson as "a top class" candidate.
"Her record of public service speaks for itself and I think she is showing with this pledge that she is an honest and open candidate." she said.