Andrew Kaye is one of the authors of 'The Tipping Point' report into how proposed welfare reforms could affect disabled people.
He says he acknowledges that changes must be made to help the economy, but believes those changes should not be aimed at 'those hardest hit'.
The UK Government says the reforms will mean money is better spent on supporting disabled people.
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Crowds came to hear him speak this afternoon in Bangor - a seat where fewer than 100 votes could make the difference at the next election.
Scattered showers with the odd heavy burst possible but there will be plenty of sunny spells too.
A rather wet and windy evening, with rain in the north and showers elsewhere.