hyphen, capital and rewording

[Tan Elaine]

Anwar was first tried on corruption charges and then for sodomy after his sacking as deputy prime minister in 1998 amid a political feud with then Malaysian premier Mahathir Mohamad.

His sodomy conviction was overturned in 2004, freeing him from a six-year prison sentence to lead a three-party opposition alliance that staged its biggest electoral success in 2008.

1. Should there be a hyphen after 'then'?
2. Should 'premier' be capitalised?
3. Is the part in bold correct? Shouldn't it be replaced by "sentence, which allowed him to lead..."

Many thanks.

 

[bhaisahab]

Anwar was first tried on corruption charges and then for sodomy after his sacking as deputy prime minister in 1998 amid a political feud with then Malaysian premier Mahathir Mohamad.

His sodomy conviction was overturned in 2004, freeing him from a six-year prison sentence to lead a three-party opposition alliance that staged its biggest electoral success in 2008.

1. Should there be a hyphen after 'then'? No.
2. Should 'premier' be capitalised? I would say not, but I think it is probably optional.
3. Is the part in bold correct? Shouldn't it be replaced by "sentence, which allowed him to lead..." No, it's not necessary "which allowed him" is understood.

Many thanks.

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