ndemning attempts by the lower federal
courts to enter exceptions to it,[660] but gradually the Supreme Court
began to interpret the provision as not prohibitive of all injunctions.
First, it has been held that an injunction will lie against proceedings
in a State court to protect the lawfully acquired jurisdiction of a
federal court against impairment or defeat.[661] This exception is
notably applicable to cases where the federal court has taken possession
of property which it may protect by injunction from interference by
State courts.[662] Second, in order to prevent irreparable damages to
persons and property the federal courts may restrain the legal officers
of a State from taking proceedings in State courts to enforce State
legislation alleged to be unconstitutional.[663] Nor does the
prohibition of Sec. 265 of the Judicial Code [28 U.S.C.A. Sec. 2283]
prevent injunctions restraining the execution of judgments in State
courts obtained by fraud,[664] the restraint of proceedings in State
courts in cases which have been removed to the federal courts,[665] nor,
until lately, to proceedings in State courts to relitigate issues
previously adjudicated and finally settled by decrees of a federal
court.[666]

In Toucey _v._ New York Life Insurance Co.,[667] Justice Frankfurter,
as spokesman for the Court, reviewed earlier cases and in effect
overruled the exception of suits designed to relitigate issues
previously adjudicated by a federal court, and held that a suit for
injunction would not lie to restrain a proceeding in a State court on
the ground that the claim had been previously adjudicated. In so doing
he placed this issue in its proper context of _res judicata_. In
addition he went beyond the requirements of the case at bar to cast
doubts upon the exception of suits brought to enjoin the execution of
judgments of State courts obtained by fraud. Furthermore, by regarding
the exception of suits restraining proceedings in State courts in cases
which had been removed to the federal courts as emanating from the
removal acts, Justice Frankfurter concluded that only one exception had
been made by judicial construction to Sec. 265, [28 U.S.C.A. Sec. 2283]
namely, that permitting injunction of proceedings in State courts to
protect the possession of property previously acquired.[668] The rule of
this case was extended on the same day to forbid an injunction to
restrain proceedings in a State court in support of jurisdiction