Metzger, a former writer for Inside Amy Schumer, has a history of harassing women and belittling their claims of sexual assault.
In August 2016, Metzger wrote on Facebook in defence of comedian, Aaron Glaser, who was banned by several New York comedy clubs after being accused of rape by multiple women.
In the since-deleted post, Metzger poked fun at the women coming forward to accuse Glaser because they had not gone straight to the police. He wrote: "Jiffy Dilfyberg [a fake name he uses to refer to Glaser] is dangerous!
"So f------ dangerous that we can't go the police to report his many rapes... the women are too brave for that."
This was not the first time that Metzger had poked fun at women who claimed to be victims of sexual assault. As reported by The Daily Dot, the comedian previously posted on Facebook that "the 1 in 4 rape statistic is bull----. It's more like 1 in 14."
Sacha Baron Cohen
Metzger is one of 10 writers for Baron Cohen's new show, all of whom are white men. The series, Who is America?, premiered on Channel 4 Monday night.
Metzger's comments surrounding the accusations levelled at Glaser forced Amy Schumer to remove him from the panel of writers for her Comedy Central sketch show.
However, the comedian has been offending feminist writers and female comedians for years before his dismissal and many fans had long expressed that they wanted him dropped from the Inside Amy Schumer team.
Schumer tweeted that she was "saddened and disappointed" in her co-worker and was "against his recent actions".
Baron Cohen's new show saw the Borat star debut four new characters and dupe a range of unsuspecting targets including Bernie Sanders, a Californian art consultant and a a number of former and current republican congressmen.
Showtime and Baron Cohen are yet to comment on Metzger's involvement in the new series.