The District's federal court admits out-of-town counsel case-by-case under Local Civil Rule LCvR 83.2(c) — a sponsored motion, a declaration, a fee, and mechanics that reward people who file there weekly.
Send the case caption and your bar details; the motion, declaration skeleton, and filing land back for signature, and admission follows in the ordinary course — these motions grant routinely when papered right. The sponsorship can be exactly that, or fold into working local-counsel support for the life of the case; the engagement letter draws the line where you want it.
With your declaration details in hand, same-week filing is the norm and same-day is achievable for true emergencies — see the emergency-filings guide for the compressed version.
Engagements are structured transparently — your client remains yours, the scope letter says so, and the court sees a conventional sponsored appearance. No surprises in either direction.
The rule asks about prior appearances within its window; frequent flyers eventually get pointed toward full admission. The declaration handles it — accurately, which is the only way.