The U.S. Capitol Police confirmed to TPM on Friday that it investigated the threat, then closed the case after determining that "there isn’t a complainant."
"Consistent with our law enforcement responsibilities, we looked into the event, determined there isn’t a complainant and have closed the matter," Shennell Antrobus, a spokesperson for the Capitol Police, told TPM in an emailed statement.
Grimm made the threat following an on-air interview in the Capitol Rotunda. The reporter, Michael Scotto, had attempted to ask Grimm about an ongoing federal investigation into the Republican's 2010 campaign fundraising.
"Let me be clear to you, you ever do that to me again I'll throw you off this fucking balcony," Grimm told Scotto in an exchange captured by a still-running camera. "No, no, you're not man enough, you're not man enough. I'll break you in half. Like a boy."
After initially issuing a statement saying he had been "annoyed" because Scotto had "insisted on taking a disrespectful and cheap shot at the end of the interview," Grimm ultimately apologized to Scotto and said they planned to meet for lunch.
On Friday, NY1 reported that the Capitol Police had contacted Scotto on Thursday, and that he told them he did not want to press charges.
This post has been updated.