What if a zero-commission broker halts trading mid-panic?
A leading zero-commission broker halting trading during peak volatility traps orders and torches user trust — the trade is reputational/regulatory hit to the broker (Robinhood-style) and a temporary liquidity vacuum in retail-favorite names. Direct rhyme: Robinhood's Jan-2021 GME trading halt, which froze buying, triggered outrage and Congressional hearings, and dented the franchise. Skeptical: market-wide impact is brief and mechanical; the broad high-beta crypto selloff overstates it — this is mostly an idiosyncratic broker/PFOF event, not a macro shock.
Every number ships with its receipt — the odds, the range, the precedents, and a public grade at Reality Check. The statistical machinery that produces it is proprietary.
The butterfly cascade
How this trigger trickles across markets, left → right — the root shock, its first‑order moves, then the ripple effects. Drag any node; tap a market for its real price history.
Resolution timeline — how this probability is moving
Our model's odds (electric blue) over time vs the market's (Polymarket, amber), from the past toward the 0–6 months horizon. Each dot is a real macro event that nudged the probability — green pushed it up, red pushed it down. Tap a dot for the source. Loading the probability audit trail…
What it would mean
If this plays out, it is a risk-off shock. A leading retail broker halts trading and PFOF flow during peak volatility, trapping millions of orders and sparking outrage. The trigger decomposes into signed root‑shocks — Volatility (VIX) ▲ · Risk appetite ▼ — which propagate through our causal graph to the markets below.