On only final sentence that was actually guilty had no foundation in law. There was no proof that Chen abused his position. Instead the judge invented a charge of "Ability of Influence (實質影響力)" to pit Chen behind bars. Just because someone might have had the ability of influence, if there is no actual proof of it, it should have been a non-guilty verdict. Or in the very least, all subsequent corruption charges should have followed this precedence and give guilty verdict to those who had the ability to influence.
However, in KMT vice chairman Lin Shiyi (林世益)'s case, the "ability of Influence" precedence was ditched and the judge went by "abusing statutory purview" or "abusing powers outside of one's statutory remit" standards that's actually the law. So even though his mom and his wife were caught hiding cash that matched the value of the accused corruption, he was given an innocent verdict.
On the other hand, DPP's Presidential advisor Chen Jenan (陳哲男) and DPP legislator Gao Zhihong (高志鵬) were also found guilty due to having "Ability of Influence." It's a KMT witch hunt, and the "Ability of Influence" bullcrap isn't even constitutional.