Sec. 8-2. Conspiracy.
(a) Elements of the offense. A person commits the offense of conspiracy when, with intent that an offense be committed, he or she agrees with another to the commission of that offense. No person may be convicted of conspiracy to commit an offense unless an act in furtherance of that agreement is alleged and proved to have been committed by him or her or by a co-conspirator.
(b) Co-conspirators. It is not a defense to conspiracy that the person or persons with whom the accused is alleged to have conspired:
(1) have not been prosecuted or convicted,
(2) have been convicted of a different offense,
(3) are not amenable to justice,
(4) have been acquitted, or
(5) lacked the capacity to commit an offense.
(1) Except as otherwise provided in this subsection
or Code, a person convicted of conspiracy to commit:
(A) a Class X felony shall be sentenced for a
Class 1 felony;
(B) a Class 1 felony shall be sentenced for a
Class 2 felony;
(C) a Class 2 felony shall be sentenced for a
Class 3 felony;
(D) a Class 3 felony shall be sentenced for a
Class 4 felony;
(E) a Class 4 felony shall be sentenced for a
Class 4 felony; and
(F) a misdemeanor may be fined or imprisoned or
both not to exceed the maximum provided for the offense that is the object of the conspiracy.
Your ex cannot bring criminal charges against you. Only the public prosecutor can do that. Your ex can provide information to the police that would result in an investigation, and if that investigation turned up evidence of you being involved in a conspiracy to commit robbery you might be charged. It is most unlikely that the police or prosecutor would be convinced to bring a charge based on the uncorroborated accusation of a former spouse. Deliberately making a false accusation against somebody is a serious crime.