Gregory's outburst was typical of someone abusing some really hard illegal drugs.
The Secret Service should do mandatory urine tests on everyone in the White House Press Corp before they are brought into the White House or even its grounds.
First Amendment to the U.S. Constitution:
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
There is nothing in the First Amendment that says the press must have access, or that public figures are obliged to speak to reporters. We have a White House press corps only out of custom that arose gradually over time, particularly over the last half-century.
I would argue that there should be no White House press corps, per se. Why should a small, elite group of reporters be given offices inside the White House, daily briefings (from which they pick and choose what to tell the rest of us), assistance with travel arrangements to follow the president around, and special access and privileges that other reporters and citizens do not get?