Political interference? An erosion of trust? The back and forth over the SNC-Lavalin controversy crested today with the prime minister adding his perspective to that of all the other players who've made their views known over the past few weeks. It's all offered Canadians a fascinating and possibly unprecedented look behind the curtain of the prime minister's office. The Agenda considers what all this is doing to Justin Trudeau's brand, the opposition's standing, and how people will vote in the October federal election.