Employee immediately accused as "Thief" by employer

Hi Experts,

I just go this scenario from another friend where his co-manager was accused as "thief" by one of his bosses. Including of which that he will be subjected for investigation and a case will be filed + opening his bank accounts. During a one on one conversation this was uttered and because he is already resigning, he was accused as such. Resignation came first.

Incident;
1. management jumped into conclusion of "theft" due to one wrong accusation from another employee that he is getting some commission or asking something or is manipulating the contracts together with the vendor.
2. No investigation yet was made, only accusations reported by one employee.
3. Accused as "thief".

Question;
1. what can the manager do to address the accusation?
2. employee manager's resignation was to effect on Dec 15. if a Preventive Suspension (PS) will be issued to him, say 30days will be stated, after the PS and no probable result was taken, will he be paid until dec 15 only or beyond dec 15?
3. Can he file a case also for such wrong accusations?

Thanks for your comments.

We are learning on this incidents. I am a starting HR practitioner.

Thank you and Godbless.

1. answer the questions truthfully if there is an ivestigation
2. employer should just accept the reignation immediately and waive the 30 day period. so nonneed to issue PS na
3. if sa harap na maraming tao sya sinabihan ng thief! thief! then he can sue for slander

Which would be best, file a formal complaint na before the management suspend them or wait for the result of the investigation?

Best for whom?

Which would be best for the employee to do? file the a case immediately or wait for the managements move?

the slander case? he can file it anytime he wants. This has nothing to do with management. Only the "boss" in his individual capacity. Medyo hard to win this case even if tutuo.
1. You have to prove beyond a shadow of a doubt that the accusations are false
-if you are charged with theft, the accuser has to prove that you did it. But when you file a charge of slander you have to prove na you did not do it. Hindi pwede mong sabihin na wala naman silang proof eh. example: ikaw ay nasa ibang bansa nung naganap ang nakawan. or nahuli na kung sino ang nagnakaw.

2. You have to prove that the person who said the false accusation had intent to cause you harm.
-example:alam nya na hindi tutuo but sinabi parin nya kasi gusto nyang masira ka sa babaeng pareho nyong nililigawan.

3. You have to prove that damage was caused to your reputation
- you have to show that certain people changed their view of you because of this incident.
- you might need sworn statements from people :eg "dati may tiwala ako sa kanya, pero magnanakaw pala sya"

But if you are confident na kaya mong i-prove these 3 things malaki ang chance mo dun sa kaso.

Thank you sir.