Recently my brother was charged with Criminal Attempt Murder, Aggravated Assault, Conspiracy Murder, Poss Instrument Of Crime W/Int and Simple Assault during a night club shooting. There were other people involved that had similar and/or less charges. After a few continuances and different court dates the judge dismissed his charges for Lack of evidence, and failure of witnesses to appear in court. However, about 3 weeks after the charges were dismissed, the DA has refiled the criminal complaint and now my brother has to start back over with the priliminary hearing all over again. If the charges were dropped what could have been the reason for re-opening the case? Could it be that the missing witnesses are willing to cooperate, new evidence or are the other parties involved be willing to make statements against him to lessen there charges.

The charges were dismissed so the DA can refile if he feels he can now make his case.

... If the charges were dropped what could have been the reason for re-opening the case? Could it be that the missing witnesses are willing to cooperate, new evidence or are the other parties involved be willing to make statements against him to lessen there charges.

Could be.

Your brother should ask his attorney about whether a speedy-trial rule or the prohibition against double jeopardy applies in his case. Chances are that they don't, but those are two of the things I would look into.