The four person panel assigned to Hamilton's case are deadlocked, and the group will have to bring in an arbitrator in order to break the tie. The panel first must decide whether Hamilton violated any rules, and then must agree on a course of treatment. The panel has not been able to agree on the latter of those conditions, which is why an arbitrator is necessary.
If Hamilton is sent to rehab, he would receive his full salary for 30 days, and then half his salary over the next 30 days. If he's suspended, but does not have to attend rehab, Hamilton would not be paid during the suspension.
MLB is also trying to determine whether Hamilton should be charged as a fourth-time offender of the drug policy. If that's the case, Hamilton could be suspended for the entire season.
Hamilton, 33, admitted to MLB that he experienced a relapse a few months ago, according to CBSSports.com Baseball Insider Jon Heyman. Hamilton has dealt with drug and alcohol issues throughout his career, and was suspended for three seasons after failing drug tests as a minor-leaguer. He met with officials in New York in February regarding the incident.