Question

what would happen if the judiciary was controlled by the executive?​

Answer 1

Answer:

It would be a formula for tyranny. The reason being that under a traditional separation of powers arrangement, the independent judiciary serves as a check on a rogue or overzealous executive. Only with the approval of the judiciary may someone be jailed long-term for (alleged) crimes.

Now, were the judiciary simply an arm of the executive, a rogue executive could easily jail all its critics and opponents. An overzealous one, even not rogue, can easily fall into confirmation bias and jail innocent people who it thought guilty due to confirmation bias. The existence of the judiciary seeks to limit that possibility by requiring the executive to prove its claims against someone to it, thereby minimizing confirmation bias that’s almost always inherent in investigators to some degree, even if they were honest.

Hope it helps