It seems to me that your employer is already conducting an investigation on this matter. Ideally what they ought to do is speak with the manager about the incident and tell him that its against company policy to push or assault another employee. And hopefully write him up on it. They ought not to terminate you, but if the manager is one w/sufficient clout and influence (ie rainmaker) they well could do so. And unless you are a union employee you may not have any legal basis to challenge the termination unless you can claim that you were discriminated when other similarly situated employees (ie same range of wage and responsibility or duty) also made a claim against the manager for pushing him/her and was not terminated. Alternatively if you engaged in protected activity, that is my manager pushed me b/c I complained about discrimination, harassment or a hostile work environment, at the work place, and if they terminate you, again you may have a cause of action under title vii and maryland state laws.