That is not quite correct. § 22–4502.01(a) creates gun free zones as described below (1000 foot buffers around schools, universities, public housing, public swimming pools; playgrounds, public libraries, youth centers, day care... ) , but this is an "enhanced penalty" for illegally carrying a gun. Basically up to 90% of DC is a gun free zone.
HOWEVER, § 22–4502.01(c) explicitly says that "(c) The provisions of this section
shall not apply to a person legally licensed to carry a firearm in the District of Columbia who lives or works within 1000 feet of a gun free zone or to members of the Army, Navy, Air Force, or Marine Corps of the United States; the National Guard or Organized Reserves when on duty; the Post Office Department or its employees when on duty; marshals, sheriffs, prison, or jail wardens, or their deputies; policemen or other duly-appointed law enforcement officers; officers or employees of the United States duly authorized to carry such weapons; banking institutions; public carriers who are engaged in the business of transporting mail, money, securities, or other valuables; and licensed wholesale or retail dealers."
So this gets confusing, and there's not a lot of case law yet on this. It seems clear that you can lawfully carry in a gun free "buffer" zone, but only if you are licensed, AND only when you are at your home or place of work within that buffer zone.
Which means you
can't carry outside of your home or work (e.g commuting??) while transiting through a gun free zone that surrounds you. And you can't carry in a buffer zone if you done live or work there.
This is a very big point in DC. I did a quick estimate of gun free zones only around daycare, elementary and high schools in an selected area of NW DC (North G'town all the way up to Friendship Heights). These buffer zones make the carry permit essentially a moot point, IMHO. Just these school areas lock up huge parts of DC
Universities would add
massive additional chunks to map below (American Univ, Georgetown, UDC would add much of the rest of NW DC ... Playgrounds and other zones would fill in pretty much most of the remainder of NW DC ... So you may get a carry license in DC, but it isn't going to let you carry very much in practice. Maybe not even as far as beyond he edge of your own sidewalk if you live within one of these many, many gun free zones.
Admittedly, these highlight just the daycare centers I know about. I'm sure there are many, many more licensed daycare facilities that fill up this map even more.
And one more funky point are the schools/daycare centers that sit on the MD/DC border. Could they creep the law to claim a buffer zone in DC around a school that is near but across the DC in MD? Sounds like tin foil, but this is DC govt of course ...
Washington Times has reported on the DC government reaction to the appeals court ruling:
http://www.washingtontimes.com/news/2017/oct/11/dc-gun-laws-defended-likely-tighten/
In that article they describe current legal restrictions on where permitted carriers can have their guns:
"The city has two sections of law that create gun-free zones. The more expansive section creates a 1,000-foot no-gun buffer around schools, day care centers, parks, swimming pools and other public gathering spaces. The law says those carrying weapons illegally in those zones can have their penalties doubled.
...
The other section of law, which includes an absolute prohibition, is more narrowly drawn. It outlaws possession in buildings associated with city government, public and private schools and colleges, medical offices, public transportation, places where alcohol is served, sports arenas, the National Mall, areas around the White House and the Naval Observatory, and at public gatherings or anywhere else the police chief officially puts off limits.
That section doesn’t have a 1,000-foot buffer zone, cutting down on collateral restrictions."
Read the full article for more information, including statements from John Lott.