I seem to often use this phrase when talking about how freedoms are balanced in a liberal society. It comes from a saying by Isaiah Berlin: "In a lake stocked with minnows and minnow-eating pike, freedom for the pike means death to the minnows." It means a freedom only for the strong or the rich.
As someone who values personal autonomy and believes that freedom should be for everyone, not just the wealthy or powerful - as someone on the left, rather than the right, in other words - I favour limiting the freedom of pikes. As Berlin pointed out, "the liberty of some must depend on the restraint of others". In order for all of us to be free, the ability of those who would limit the freedom of others must be restricted.