The letter from the elders is an astonishing example of a denial of natural justice. Advising a sister that she has been accused of apostasy is one thing, but how would it be possible for a person to arrive at a trial (sorry, judicial committee) prepared to make an adequate defence?
Precisely what was the act of apostasy? Where was the act committed and when?
Who has made this accusation? What is the basis of their accusation? Can the accused sister challenge or question the accuser? Will certain Bible scriptures be cited as evidence of a breach of proper Christian conduct? If so, which ones?
In a criminal trial, all this information is provided to a defendant in advance so they can prepare their defence.
In the case of a JC, a sister is expected to arrive at a hearing knowing none of those things. She will be informed of the charges, then, with no prior preparation and denied the opportunity to seek advice or support, be required to answer a series of back-to-back questions by three men who have had weeks to prepare for the meeting and anticipate her responses. Any chance to seek an adjournment to consider her position would be taken as defiance and obstruction.
She will not be allowed to record proceedings should she later wish to appeal a guilty verdict. If found guilty, members of the congregation will have no access to either the allegations or the reasons for the committee's decision. They will simply learn through gossip than a judicial hearing was held and that the result was a decision to disfellowship. There will therefore be no provision for other members of the congregation (including family or other elders) to consider for themselves whether the decision was correct.
These are the tactics of a tyrannical tinpot dictatorship that conducts its judicial activities in a climate of fear, surprise and secrecy, so unsure of the rightness of its actions that it ensures they can never be examined.
Anyone who walks into a judicial committee in those circumstances should know that a decision has already been made.