Using 聴く instead of 聞く to mean "ask"?

Question

I am reading this article on NHK, but I am having a hard time understanding the title...

緊急事態宣言出すのを前に諮問委員会始まる 専門家に意見聴く

for the first part 緊急事態宣言出すのを前に諮問委員会始まる

I am having a hard time parsing this. I understand:

緊急事態宣言出す - releasing the declaration of the state of emergency

諮問委員会始まる - Advisory committee begins

What is throwing me off is the 前に after the のを...

if it was:

緊急事態宣言出すのを諮問委員会始まる - The advisory committee will begin the releasing of the declaration of the state of emergency.

or

緊急事態宣言出す前に諮問委員会始まる - The advisory committee will begin before releasing of the declaration of the state of emergency.

So what I think it means is this?! is it correct?

緊急事態宣言出すのを前に諮問委員会始まる - The advisory committee will begin the releasing of the declaration of the state of emergency before. (before what??)

Now for the second part

専門家に意見聴く - Asking the opinion of a specialist.

Why are they using 聴く and not 聞く or 訊く?

if it was

専門家の意見（を）聴く - Hearing the opinion of a specialist.

I would be fine with it....

Answer 1

The particles を, が are omitted. The sentences are using "headline grammar". See:

• what is the name of the abbreviated writing style used in newspapers?

緊急事態宣言出すのを前に諮問委員会始まる 専門家に意見聴く

to rewrite it in normal grammar:

緊急事態宣言を出すのを前に諮問委員会が始まった。専門家に意見を聴いた。

literally:

"Prior to releasing the declaration of the state of emergency, the advisory committee began. (They) heard opinions from experts."

In 「～のを前に」, the の is a nominalizer. For 「Noun+を前に」"before/prior to~", see:

• How does one analyze "N + を前に + V", where N is not an object of V

聴く looks more like "hear (someone's opinion)" or "listen (to someone's opinion)" (≂「耳を傾ける」) than 聞く which can be "ask (opinions from...)" (≂「(意見を)求める」). eg 公聴会

専門家の意見（を）聴く - Hearing the opinion of a specialist.

I agree that strictly grammatically, 「専門家の/から意見を聴く」 or 「専門家に意見を聞く」 would look more correct than 「専門家に意見を聴く」.