New York Rep. Michael Grimm stole the show — and not in a good way — on State of the Union night when he was caught on camera threatening a reporter for a New York TV station for asking about an ongoing federal investigation into whether his campaign solicited and accepted money from foreign donors.

While it's easy to exaggerate the potential impact of Grimm's behavior on SOTU night — he certainly still seems more likely to lose reelection because of the ongoing Justice Department probe than for telling a reporter he'd like to break him in half (is that even possible?) — the Staten Island Republican made a number of rookie mistakes in how he handled the interview with NY1's Michael Scotto.(Grimm, of course, apologized for his behavior this morning.)

1. Don't agree to an interview if you don't want to answer questions. Here's the thing: Reporters ask questions like it's their job because, well, it's their job. So, if you agree to an interview, you need to be ready to answer the questions asked of you.

2. If you walk out of an interview, just keep walking. Grimm, unhappy with Scotto's line of questioning, walks away. Okay, that's his right. But then he comes back to scold and threaten Scotto. Imagine if he had just kept walking? This story probably isn't a story at all. "Congressman threatens reporter" is a very different storyline than "Congressman ends interview abruptly."

3. If you are planning to have a meltdown, don't do it on the one night a year people are paying attention to Congress. Yes, we know ratings are down for the State of the Union speech. But millions of people still watch the speech and consume the coverage in its aftermath. There are also roughly one bajillion reporters on Capitol Hill into the wee hours of the night to cover the president's speech. It's literally the single worst night of the year to have a blowup.

4. If you are planning to have a meltdown, don't do it on camera (and with a mic sort of on). Grimm had JUST walked out of the interview with Scotto. Why would he think the camera that had been on seconds before would suddenly be turned off? Or that a mic might not pick up this modern classic: "Let me be clear to you, you ever do that to me again I'll throw you off this f***ing balcony."

5. Don't issue a statement that doesn't apologize. It's hard to imagine that Grimm could have made things worse after confronting Scotto on camera — but then he did. This statement, released by Grimm in the immediate aftermath of the confrontation, is one for the ages.

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