If son locks room of toperty owned by his father

It is believed that father is Hindu.

If the property is self acquired by father then anyone i.e wife, mother, children have no forced share in life time of owner/father.

So the act of son, even if he is a lawyer, is illegal.

Since he is a lawyer and is issued a sanad,he is expected to live a law abiding life.

The complaint with police,court,DBA,Bar can be lodged.

The father can dispose the property in his life time in any manner as it pleases to him by a valid deed e.g: WILL, sale, trasnfer, gift, mortgage etc

Looking into the situation it shall be better to register the WILL.