Are leading questions permissible?
Rule 611(c) provides that leading questions are generally not allowed on direct examination, except to develop a witness's testimony. However, this rule and its corresponding notes do not define leading questions or address whether closed-ended questions are inherently leading.
Leading questions are objectionable when you're asking them of a third-party witness, but they are not objectionable when you're asking questions of the adverse party.
The use of leading questions in court to elicit testimony is restricted in order to reduce the ability of the examiner to direct or influence the evidence presented.
Leading questions are also allowed during a cross-examination when an attorney is questioning the other party's witnesses. This is because one of the purposes of cross-examination is to test the credibility of statements that a witness made on direct examination.
In general, leading questions are not allowed during the direct examination of a witness, however, they are allowed on the cross-examination of a witness.
Leading questions can only be asked during cross-examination and not during examination-in-chief or re-examination unless and until the court allows.
Use leading questions with care. If you use them in a self-serving way or one that harms the interests of the other person, then they can, quite rightly, be seen as manipulative and dishonest.
Leading questions are the most obvious examples of bias to spot, as they make it very clear that there is a “correct” answer the question is leading you towards. These will always result in false information as the respondent was never given the option for an honest response to begin with.
Leading questions allow you to control what the witness talks about and often helps you get the witness to give a specific answer. You cannot ask leading questions of the witnesses you call.
(1) A party may put a leading question to a witness in cross-examination unless the court disallows the question or directs the witness not to answer it.
What is wrong with leading questions?
Leading questions result in biased or false answers, as respondents are prone to simply mimic the words of the interviewer. How we word these questions may affect the user response and also may give them extra clues about the interface.
Tips to Rephrase a Leading Question
If the judge sustains an objection to a leading question, focus on rephrasing the question so that it no longer suggests an answer. In other words, try for a more "open-ended" question.

To reply to a loaded question, you should first recognize that the question being asked is loaded, and then either reject the problematic presupposition, point out the fallacious reasoning involved, or refuse to answer the question.
a question asked of a witness by an attorney during a trial or a deposition (questioning under oath outside of court), suggesting an answer or putting words in the mouth of the witness.
The rules about cross-examination aren't as strict as they are for direct examination (when you question your own witnesses). For example, in cross-examination, you can: ask leading questions, and. challenge the other party's evidence (that is, try to show that it's not reliable or correct).
Leading questions shall not be used on the direct or redirect examination of a witness, except that the court may permit leading questions, in its discretion, in circumstances such as, but not limited to, the following: (1) when a party calls a hostile witness or a witness identified with an adverse party, (2) when a ...
A leading question is one that suggests the answer in the question itself, and thus is an impermissible technique of trying to "lead" the witness to the desired answer.
You cannot be punished for refusing to answer a question. It is a good idea to talk to a lawyer before agreeing to answer questions. In general, only a judge can order you to answer questions.
The comment to Section 767(a) also allows leading questions on direct examination for “refreshing recollection, and examining handicapped witnesses, expert witnesses, and hostile witnesses.” When calling an expert, then, the California evidence rules do not require that a lawyer refrain from asking leading questions.