If p-and-ds are illegal, why can the stock keep trading the entire way up AND down?

This is something that bugged me for months. Every morning there's a sub-$5 name up 120%+ or something, on nothing, retail piles in, it collapses, and maybe months later there's an investigation. If manipulation is illegal, how is the stock allowed to trade the whole time it's happening?

The answer I landed on is this. Securities law doesn't ban a stock from moving violently. It bans the *conduct* used to manipulate it, such as, coordinated trading, undisclosed paid promo, lying to investors. But a 150% move, a tiny float, a reverse split, an insider selling, none of those are illegal *by* themselves. They're just red flags. The actual crime is hidden in the connections (who controlled the shares, who paid the promoter, who coordinated), and proving that takes bank records and messages, not a chart.

So by the time regulators can act, the round trip from $1 to $8 to $1 is already done. Enforcement ends up being a cleanup crew, not a barrier. Retail doesn't lose money when the case is announced but during the quiet investigation before it.

Curious what this sub thinks: should a stock get auto-halted when it rips 150% with no filing? Or would that just wreck legit small caps?