 Re: Confused about the two clauses joined by the relative pronoun WHOM.
1. First of all, let's sort out the basic grammar of the sentence. Judge is a singular, countable noun and here a specific judge is being referred to. So you need the :
The Judge to whom...
Interestingly the same argument should hold for plea, but in fact in legal English it is often used without an article in the expression to enter plea. Legal English tends to have a grammar of its own that may differ from every day usage. However, you need to remember that legal English is a very formal variety, so automatically if you choose "legal English grammar" the text has a formal style and more informal elements can't be used. This is also marked by the use of to whom rather than who .....to, so in this case the omission of the article is coherent with the overall style.
2. Now to your question...
Sentence (a) makes no sense at all. The verb give must have both a direct and an indirect object. It would have to be, as in sentence (b) :
The judge to whom he will enter plea gave money to his campaign.
At that point the two underlying clauses are as you analyse them :
- He will enter plea to the judge
- The judge gave money to his campaign |