Can provincial NDPs and federal party unite?

The federal NDP selected Avi Lewis as its new leader on Sunday, drawing immediate criticism from the Alberta and Saskatchewan NDP as they attacked Lewis for past comments and his stance on fossil fuels. Lewis joins Power & Politics to defend his policies and his vision for restoring a caucus reduced to six seats. Plus, Housing Minister Gregor Robertson defends his nationwide progress on housing despite what he calls a 'challenged' Ontario market.