Explain this to me like I am a six year old...

By now, every sane American has been informed that contrary to popular belief the concept of "quid pro quo" is not an illegal action in and of itself. However, Democrats (and their liberal cronies in the lame stream media) argue that what Trump did with the Ukrainians and their military aid was in fact corrupt and impeachable because he was attempting to:

Dig up dirt on his opponent

But if you drill into this allegation "logically" it requires Democrats to prove certain things, considering they are the accusers and therefor own the burden of proof. One of the main things that they need to prove (in order to show corrupt intent) is to prove that any requested investigation would be baseless and unnecessary.

Keep in mind that Democrats have argued now for over three years that investigations that harm the President politically do not spring from this same sort of "corrupt intent" because the investigations themselves are warranted and questions need to be answered. In spite of zero evidence EVER uncovered that Trump and campaign were somehow Russian agents, many Democrats are still demanding that we continue to go down that path.

So logically, in incumbent on Democrats to "prove" (not just allege) that investigations into Ukraine's involvement of the 2016 election and investigations into Burisma and Hunter Biden are actually baseless. Just making the statement is not good enough, and provides zero proof that Trump was calling for baseless and unwarranted investigations.

They have to "prove" the allegations, not just make them. That is the fundamental reality of our criminal justice system.

So it is literally the Democrat's burden to prove (not just allege) that investigations in 2016 election activities and Burisma holdings are unwarranted and baseless. They will have to show this beyond all doubt. Yet, Schiff and the Democrats are on record as saying any questions about the 2016 election, Burisma holdings, or Hunter Biden are off limits? Yet these are the investigations that they need to PROVE  are unwarranted?  It's like accusing someone of murder, and claiming that you don't actually have to prove that someone was killed.

To repeat: they literally cannot prove corrupt intent (and justify impeachment) without PROVING that the investigations are unwarranted. That is their burden. But even if they laid that burden on the President (make him prove that they are warranted), they are literally refusing to allow him to wage any sort of defense to do so?

Explain to me like I am a six year old how you can prove your case, if you refuse to even acknowledge, much less allow any witnesses or discussions of the main issue that you allege?