An employer found out that his worker has been stealing money from his business for some time. Though he has not caught him red handed, the overwhelming circumstantial evidences leaves no doubt at all about the thefts. However the worker stubbornly refused to admit his wrongdoing. What is the Islam ruling if the employer straightaway cut the wages of the worker to cover his loss due to the theft as it would not be worth the trouble to bring the case to the court?
In Islam, if a husband walks in on his wife having intercourse with another man he can not do anything unless he has 4 other witnesses or swears upon Allah that she did it -at which she can swear she didn't and she is free to go as Allah mentions in the Quran:
واللاتي يأتين الفاحشة من نسائكم فاستشهدوا عليهن أربعة منكم
The same thing is true with all crimes in Islam, the person must be caught in the act of stealing and not just from one person, unless the person confesses his crimes.
Lawfully speaking, if you take a person to court or the police with circumstantial evidence (even if they are overwhelming), it is all that is, circumstantial and will be thrown out of the court.