The Commons ethics committee is in an uproar again Thursday as it wrestles with the issue of Conservative ad spending in the last federal election.

A former Tory candidate began shouting at MPs after he showed up unannounced and demanded to be heard.

Sam Goldstein, a lawyer who ran for the party in Toronto and participated in the party's "in and out" advertising scheme, began yelling at committee chair Paul Szabo and NDP MP Pat Martin as the panel adjourned for lunch.

The hearings into the ad scheme have been a raucous affair all week, with witnesses refusing to appear and Tory members of the committee accusing Szabo of partisanship.

Goldstein didn't show up on Tuesday as he was summoned to do, but said he was involved in a trial at the time and couldn't make it.

The committee is looking into Elections Canada allegations that the Tories wrongly attributed $1.3 million in ad spending to local candidates, instead of the national party.