Get the news involved and make an example out of them. Write letters to your higher ups and so. THIS SHALL NOT STAND!
EDIT:
Source:
http://www.weblocator.com/attorney/ca/law/c06.html (not sure if this is accurate)
Acceptance
In order for an acceptance of an offer to be valid, the acceptance must be made while the offer is still open. In some situations, the person making the offer gives a definite time frame so the offer ends when the time has elapsed: "I will sell you my car for $200 but you must decide whether to buy it within two days." Other ways an offer may end include: the person making the offer withdraws the offer, the person who receives the offer rejects it, a reasonable amount of time passes after the offer is made, or the subject matter of the offer is destroyed before acceptance.
If a person changes the conditions of the offer in responding, the offer is rejected and a counteroffer is made as in "I will buy your car, but I will pay only $150 for it." In this scenario, the person who made the original offer responds to the new offer by accepting it, rejecting it, or proposing yet another offer.
There are two ways a person accepts an offer: by promising to do or not do something, or by performing the desired act. In the first type, a person responds to an offer to sell a car for $150 by promising to pay $150 for the car. This is called a bilateral contract. In the second type of acceptance, a homeowner offers a neighbor $10 to cut his or her grass and the neighbor responds by cutting the grass; the neighbor accepts the offer simply by performing the act requested. This is called a unilateral contract.