Sudhakar didn't do anything illegal, but there were valid reasons for Abhijeet to get angry with him
1. He threw around his authority as CID officer and refused to open the dikki...anyone - common citizen or CID officer must comply with rules.
2. After he refused to open the dikki, the dead body was found in the dikki and so everyone was suspicious.
3. Somehow Sudhakar didn't openly tell everything to Abhijeet. He didn't tell Abhijeet that he knew the dead man - the bank manager where he had approached for loan.
4. He just ran away from CID custody.
5. ACP wasn't there and the DCP was sitting on top of Abhijeet's head and so he was under additional pressure.
And Sudhakar was also under tension, so he just took it out by calling Abhijeet names.
Such things happen between colleagues.