Understanding the Presidential Pool Spray and What Happened to CNN's Kaitlan Collins

It can be rowdy and even rude at times. But the media "spray" — shouted questions by the White House press corps to the president — is a necessary part of holding the nation's top public official to account.

On Wednesday, White House aides banned CNN reporter Kaitlan Collins for shouting questions Trump did not like, setting off a national debate about how the press does its job.

Here are five things to know about the presidential pool spray.

HOW IT WORKS
It is standard protocol for reporters to ask the president questions at sprays, and Trump, unlike some of his predecessors, often engages.

Typically, the White House announces that a closed presidential event will include a "spray" at the top, which means a small "pool" of journalists representing print, radio, broadcast and wire services will be invited into the room at the beginning. The images and video usually feature a dozen or more journalists clad in IDs, headphones and gear, crammed into a small space and hoisting long, furry microphones toward the president. Sprays happen in such places as the Oval Office, at Cabinet meetings and other confabs the president wants in images or on audio.

THE GOAL
The president gets the publicity he wants — footage, say, of his hand-shake with another head of state or signing key legislation into law. His goal overlaps with the media's aim of broadcasting these events to the world.

Etiquette dictates that no questions are asked until the president makes any remarks. But that's where aligned interests, and sometimes the dignity of the occasion, ends.

Reporters can then ask any question on any topic. Sometimes they shout to make sure the president can hear the question.

WHAT'S DIFFERENT NOW
What's new is Trump's engagement — he's answered questions on everything from his alleged former mistress Stormy Daniels to Russia's meddling in the 2016 presidential election during these brief media hits.

The former reality show star's habit stands in contrast to other presidents, many of whom saw more risk in answering questions off-the-cuff.

Former President Barack Obama, for example, disliked rowdy pool sprays and rarely answered shouted questions in the informal settings. The WHCA often fought with his administration over the matter.

By Obama's second term, frustrated reporters crafted a list of what it considered best practices for a president. These included taking questions from the press no less than once a week.

WHAT HAPPENED WEDNESDAY
At an Oval Office pool spray early in the day, Collins — representing television networks — was one of the reporters peppering the president with questions. Some of her queries focused on an audio recording of Trump taken by his former lawyer, Michael Cohen, about a tabloid payment to a woman alleging an affair with Trump.

White House staff at one point shouted at reporters to leave the room. Later that day, according to Collins and CNN, she was reprimanded by press secretary Sarah Huckabee Sanders and communications chief Bill Shine and barred from a Rose Garden event, which was open to all other members of the credentialed media.

The White House said it found Collins' questions inappropriate. Multiple media outlets, including Shine's former subordinate at Fox News and the White House Correspondents Association, condemned the move.

'THANKS,' NOW GET OUT
Wrangling the press at sprays can get complicated in the Trump era, because the impulsive president will listen to the shouted questions — and sometimes answer the ones he likes.

After the president gets the images and audio he wants, White House press aides seeking to keep the president "on-message" will sometimes try to out-shout the shouting reporters, hollering, "THANK YOU!" which keeps Trump from hearing the questions in the first place. The result is a lot of yelling, which can look and sound chaotic on television.