President Obama is known for keeping his emotions in check, but on the issue of gun control, the emotion flows freely. (Peter Stevenson/The Washington Post)

President Obama wants new gun control measures — specifically background checks at gun shows — but he also wants something else: media scrutiny on the firearms record of Republican presidential candidate Chris Christie, who over the weekend called Obama a “petulant child” for taking executive action on causes that seem unlikely to pass in Congress.

This was White House press secretary Josh Earnest on Monday: “I do think it’s probably worth taking a close look at Governor Christie’s record on some of these issues in particular to see whether or not he has changed his position in an effort to try to round up votes in a Republican presidential primary. I’ll leave that up to you guys to decide.”

What is the media supposed to do with that? An examination of Christie’s gun control history now looks like an obliging “yes, sir,” to White House marching orders — not a good look for independent journalists. But gun control is one of the major issues of the moment, and it’s always important in New Hampshire, home of the first-in-the-nation primary, where Christie has invested heavily. So, the press can’t really ignore it, either.

Fortunately for journalists, Earnest’s suggestion seems to be based on the faulty premise that Christie’s gun record hasn’t been vetted already. It has — by CBS, NBC, Fox News, Mother Jones, the Star-Ledger  and others.

To review: Christie said in a statement announcing his candidacy for state Senate way back in 1993 that “the issue which has energized me to get into this race is the recent attempt by certain Republican legislators to repeal New Jersey’s ban on assault weapons. In today’s society, no one needs a semi-automatic assault weapon.”

In other words, preserving certain restrictions on gun ownership was not merely a small part of Christie’s platform early in his career; it was a driving force behind his decision to enter politics in the first place. And as recently as 2013, the New Jersey governor trumpeted his signing of 10 “commonsense measures [that] will both strengthen New Jersey’s already-tough gun laws and upgrade penalties for those who commit gun crimes and violate gun trafficking laws.”

Lately, however, Christie has emphasized aspects of his record that appear more friendly to gun owners, such as his decision to veto a 2014 bill that would have reduced the permitted size of ammunition magazines from 15 rounds to 10. His presidential campaign website states that “Chris Christie will not allow political agendas to further restrict the rights of law-abiding gun owners, and as governor of New Jersey he has fought to defend gun rights.”

This has all been reported already, so the media can safely reference what might best be described as Christie’s mixed record on gun control without looking like Obama foot soldiers.

But memo to the White House and all politicians who might be tempted to tell the media what to cover: Don’t. Just don’t. Even if you get your way, you risk undermining the ensuing reports by making them look like the result of your attempted puppeteering. Or, as in this case, you might appear to be wishing for something that has already been done. Extensively.