Three students from the Massachusetts Institute of Technology remain mired in a legal battle more than a week after they were scheduled to give a presentation at the Defcon convention.

The students had planned to present research into a hack of the Charlie payment system used by the Massachusetts Bay Transit Authority (MBTA).

Transit officials filed suit with a judge earlier this month to prevent the students from delivering the presentation, which the MBTA claims will allow others to manipulate the system and avoid paying fares.

The MBTA won a preliminary decision last week from a federal judge who placed a temporary restraining order on the students.

The latest round in the battle concerns whether the judge will issue an injunction to further prevent the students from disclosing the information or lift the restraining order.

MBTA attorneys argued in an interview with The Boston Globe that the students had not turned over enough information on the report and were not complying with the judge's original order.

The students claim that the MBTA had asked only for a vulnerability, which was given, and that they believed the matter to be resolved.

The Electronic Frontier Foundation, which is representing the three students, has claimed that MBTA officials were given all the requested information.

The privacy group cited a filing from an MBTA Transit Police detective which suggests that the students had agreed to provide a vulnerability report and that the officers did not believe the research had violated any laws.