The Chaser’s comedians are often attacked when their jokes misfire, but former Chaser Charles Firth was still amazed to be ambushed by ACTU boss Jeff Lawrence at the union movement’s media dinner in Melbourne last week.

According to our sources, an emotional Lawrence “embarrassed” other dinner guests in the Crowne Plaza’s restaurant by yelling at the funnyman, and telling him he had “crossed the line” and gone “way too far”.

Firth’s crime? He had made a joke about Australia’s largest blue-collar union, the AWU, and its self-promoting national secretary, Paul Howes. Welcoming workers from all across Australia, Firth had quipped that the bosses were also represented, and that you could tell them by the AWU logo on their sleeves.

Within minutes of resuming his seat, Firth was set upon by the ACTU leader, who had perhaps received a complaint from someone in the AWU.

When news of Lawrence’s tirade spread through the room, one drunken conference delegate lowered the tone even further by shouting out, “Paul Howes is a f-cking c-nt! What a f-cking w-nker!”

Before long, conspiracy theorists and Chinese whisperers were surmising that a delegate at the dinner had tipped off Howes, who had urged Lawrence to deliver a dressing down to Firth for his cruel jibe.

But this is fanciful and quite clearly wrong.

When The Power Index phoned the up-and-coming union boss this morning, Howes told us he knew nothing about the incident, had not been at the dinner and had not even heard any reports.

And in a poignant comment on his exclusion from our Top 10 Political Fixers list, he signed off, “I wouldn’t know. I’m not very powerful. You’d better talk to someone who is.”

The Power Index is still hoping for a comment from Jeff Lawrence, who was in meetings this morning.