WTO Trade Dispute Backlog — 2D Queueing Simulator

Appellate Body Bench

Seated judges 0 / 7

Quorum (needs 3) No

Dispute Filings

Filing rate 40 cases/yr

Time speed 1.0 yr/s

Docket

Simulated year

0.0

Resolved

Backlog

Avg wait

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How it works

The WTO's Appellate Body needs at least 3 of its 7 seats filled to hear any appeal (a "division"). Since the US began blocking judge reappointments in 2017, the bench has been below quorum since December 2019 — every appeal since then is, in the WTO's own words, an "appeal into the void": filed but legally unable to be heard.

quorum:     judges ≥ 3
panels:     P = floor(judges / 3)
throughput: T = P · μ        if quorum met
            T = θ · μ_mpia    if not, and MPIA active
            T = 0             otherwise
backlog:    dB/dt = λ − T
avg wait:   W ≈ B / T   (Little's Law, L = λW)

μ ≈ 6 resolved cases/year per 3-judge panel. The Multi-Party Interim Appeal Arbitration Arrangement (MPIA) is a 2020 workaround: only about θ ≈ 30% of WTO members opted in, and it clears cases through ad-hoc arbitrators at a slower rate μ_mpia ≈ 4/yr — it does not restore the treaty body itself.

Seated judges slider — drag to 0 to reproduce the real 2019–present gridlock, or to 7 for a fully staffed bench, and watch the backlog curve invert.
Filing rate — how many new disputes members bring per simulated year.
MPIA workaround — toggles the interim arbitration trickle when the bench itself is empty.
Drag inside the canvas — pans the backlog-pile view; scroll/pinch zooms it.
The bottom strip is a scrolling chart — toggle it between backlog and resolved-vs-filed throughput.

Occupied judge seat Empty seat Pending dispute Resolved dispute