The main game

ASADA and the AFL have alleged through infraction notices that the supplements program implemented at Essendon during 2011-2012 included the banned substance thymosin beta-4.

It is estimated that as many as 20 of the 34 players remain on Essendon's list heading into the 2015 season. The players' identities have not been disclosed, although it's believed the support staff person in question is Stephen Dank, the architect of the supplements program.

A three-person panel, known as the AFL Anti-Doping Tribunal, will hear the case and deliver a verdict.

The rules

The players will be prosecuted as one group. The hearing will operate basically as any another AFL tribunal, with the prosecutor outlining the case for, and the defence responding, with the right to cross-examine each other's witnesses in play.

Venue and time

The hearing will be held in the County Court of Victoria. It will be closed to the public and the media, although the tribunal has resolved to provide "regular statements informing the public of progress". It begins on Monday and will continue on December 18 and 19, resuming after Christmas on January 12. It is unknown how long the complex case – considered to be the first of its kind – will run. The players are not required at the hearing and won't attend, but can view the proceedings via a live video stream. Dank is not expected to attend, either.

The burden of proof

The term used is "comfortable satisfaction", which is lower than "beyond reasonable doubt", but significantly higher than the balance of probabilities. ASADA carries the burden in this case because no Essendon player issued with an infraction notice has tested positive for thymosin beta-4. Had positive drug tests been present, it would have been up to the players to effectively prove their innocence. Essentially, ASADA will try to prove the "who, what, where, when and how" of every alleged administration of thymosin beta-4.

ASADA's case

The allegation is that convicted drug dealer Shane Charter sourced the raw materials for the banned substance, which he then passed on to South Yarra-based chemist Nima Alavi, who compounded the materials into thymosin beta-4. It is then alleged that Alavi gave the substance to Dank, who administered the drug to the players. It's expected that ASADA will outline a "perfect match" between the frequency of injections at Essendon during the period in question and the accepted protocol for administering thymosin beta-4.

It's understood the players have provided written documentation of what drugs they believed they used in the program, and also signed documentation of the number of injections they received per week. Those records as well as interview transcripts – most importantly with the key players Charter and Alavi –  as well as text messages, emails and a catalogue of other circumstantial evidence are expected to be used.

Players' response

The players have remained steadfast in their belief that the injecting program used no illegal substances. Should the tribunal find otherwise, the players would argue that any illegal administering by Dank was done without their knowledge and consent – and despite several attempts on the players' behalf to ensure the program complied with all relevant drug codes. The key point in this case will be whether the players were given the legal drug "thymomodulin" – also referred to as "thymosin" or "thymosin Alpha" – or thymosin beta-4. The players' response will include a catalogue of circumstantial evidence rejecting ASADA's claims.

Missing pieces

ASADA never interviewed Dank during the investigation. He has maintained that he never gave the players anything illegal. He expressed a desire to testify at this hearing, but only if it were open to the media and public, which it is not. He has stated that he administered the legal form of thymosin. However he once admitted in an interview with a Fairfax Media journalist that he injected the players with thymosin beta-4. He quickly changed his version of events after being told that the substance was banned. This exchange has been reported and will form part of ASADA's case. ASADA's failed bid in the Supreme Court to force Charter and Alavi to testify has been viewed as a significant blow to its case.

Key participants

The majority of the players will be represented by David Grace, QC, who is the president of Athletics Australia and has been a member of the Court of Arbitration for Sport. Two players enlisted separate counsel. ASADA's main prosecutor will be Malcolm Holmes, QC, an internationally recognised Court of Arbitration for Sport member who sat on a three-member panel charged with investigating corruption in world cycling after Lance Armstrong's demise. The AFL will be represented by its senior lawyer, Jeff Gleeson, SC. The three members of the tribunal will be chairman David Jones, QC, former County Court judge John Nixon and barrister Wayne Henwood, a former AFL player. Dank has been represented by his lawyer Gregory Stanton throughout the process.

The stakes

The players face a maximum two-year suspension if found guilty of taking thymosin beta-4, but that sentence could be reduced to six months and part of it back-dated depending on what evidence emerges. The World Anti-Doping Authority has the power to appeal any suspension.