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Popular ridesharing service Uber finds itself on the defensive after an executive made controversial comments last week suggesting the company dig up dirt in an effort to besmirch the reputations of journalists who have been critical of the transport service.

In response, Minnesota Sen. Al Franken has sent a letter to Uber CEO Travis Kalanick, requesting that he address a series of questions stemming from the recent comments made by Senior VP of Business Emil Michael at a dinner party.

At the conclusion of the three-page letter, Franken asks that Kalanick provide his responses by Dec. 15.

In addition to the troubling comments, Franken expresses his uneasiness over reports of a "God view" tool, which purportedly "allows employees to track the location of Uber customers who have requested car service," per the congressman's letter.

Franken's letter, which was dated for Wednesday, came just one day after Kalanick published a series of tweets apologizing for Michael's remarks. Kalanick wrote that "Emil's comments at the recent dinner party were terrible and do not represent the company."

He added that the "remarks showed a lack of leadership, a lack of humanity and a departure from our values and ideals."

Franken isn't the only prominent figure pressing Uber in the wake of Michael's comments. One of the tech journalists Michael specified, Sarah Lacy believes the $18 billion company isn't being held accountable.

"I've been really concerned since about 2012 of an escalating culture of bad behavior in Uber that never gets checked. The board and investors seem to be scared of [CEO] Travis Kalanick. No one really holds this company accountable," she told CNNMoney.com.

On top of criticizing how the company handles assault complaints from female passengers, Lacy notes a recent Uber promotion that proposed free 20-minute rides with beautiful models behind the wheel. The company quickly canceled the campaign and issued an apology after receiving immediate backlash.

Although Uber has undoubtedly been successful over the course of its brief existence, a series of missteps have critics piling up. And with a member of Congress now joining the fray, Kalanick and Uber will have to find a way to reassure customers and regain whatever trust that has been lost.