Niles received 23 votes from the States - more than half the eligible voters.
He was Policy and Resources' preferred candidate, and was put forward by the President, Deputy de Sausmarez:
"He will, I have no doubt, bring breadth, depth, and robustness to the committee's thinking.
"He is, as I know from working with him, and as many others will attest, both thoughtful and pragmatic - qualities which will stand the Committee in good stead in delivering its sizeable mandate.
"P&R is at its strongest when it draws on a range of experience, perspective and approach. and when it combines political insight with commercial understanding and a clear focus on delivery."
Andrew Niles himself said he will 'think differently' and is not 'driven primarily by ideology', instead is far more interested in 'outcomes, delivery, and whether something actually works.'
He is the Vice-President of the Committee for Economic Development and the States' Trading & Supervisory Board.
Others vying for the seat were Deputy Haylay Camp, receiving 5 votes, and Gavin St Pier.
The space was vacant due to St Pier's resignation earlier this month, to test if he had States support for a senior role. He received 11 votes.
It's after being questioned by police over harassment allegations, which he denies, and during the election debate, he appeared to ask the States to overlook:
"Whilst enquiries are ongoing, it is unnecessary that the States should be without the best team on the pitch... With humility, I submit that members know I am the best available and most experienced candidate in this election today."
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The vote comes at a key time as Policy and Resources is due to publish tax proposals for the island in early June.
READ: Cuts to services in Guernsey considered under tax review
And, it is the second seat lost and re-voted for during the term, after Jonathon Le Tocq's resignation for sexual offences.
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