Single word for logical but obstructive responses

Question

Consider the following situation.

A prosecutor in court is asking questions of an expert witness. The responses are all negative with the expert always adding another explanation to the prosecutor's conclusions/diagnoses. The expert witness's attitude could be interpreted as obstructive but logical. The questioning continues and the responses are appropriate for the question but continue being negative.

The prosecutor feels that the witness is being [adjective I'm looking for] in their responses.

I know the word exists, but I've forgotten it.

Answer 1

evasive [ɪˈveɪsɪv]
adj
1. tending or seeking to evade; avoiding the issue; not straightforward
2. avoiding or seeking to avoid trouble or difficulties to take evasive action
3. hard to catch or obtain; elusive

verb = evade.

pre•var•i•cate (prɪˈvær ɪˌkeɪt)
v.i. -cat•ed, -cat•ing.
to speak falsely, misleadingly, or so as to avoid the truth; deliberately misstate; equivocate; lie.
[1575–85; < Latin praevāricātus, past participle of praevāricārī to straddle something, (of an advocate) collude with an opponent's advocate]

adj = prevaricative
adv = prevaricatively

Wikipedia:Evasion: Evasion is, in ethics, an act that deceives by stating a true statement that is irrelevant or leads to a false conclusion.

Evasion and evasiveness are usually and annoying practiced in responding to questioning, in court or by legal parties, by providing logically true but deceptively inaccurate and insufficient responses.

Answer 2

In the given context of legalese, the party is said to be being vexatious, or indulging in vexatious argument.

vexatious vex·a·tious vekˈsāSHəs/ adjective Law
denoting an action or the bringer of an action that is brought without sufficient grounds for winning, purely to cause annoyance to the defendant.