"In recent months we have seen and heard of many instances where Parliamentarians standards of behaviour have been under the spotlight, including sexual abuse, bullying, deceitful practices, sheer rudeness and arrogant behaviour".
That paragraph says it all, that really is normal behavior for the party whips, they don't actually use sex abuse directly but any dirt they have ( and they have a lot ) they use to persuade MPs to tow the party line. You may not realise but that extends right down to local councils, step out of line and you are out, that's what party Local Agents do. ( a friend of mine was kicked out for disobeying the party line )
Bullying in this way is what makes political parties strong, many MPs start as local councillors, wanting to serve the community, all quickly learn its serving the party machine that counts.
Can we change that, NO, we can replace those that get caught, the illusion that all those that we give power to are going to be honest and decent does not exist. That is true of all political elites wether democratic, socialist or communist. The only saving grace is that in the UK political misbehavior is much less prevalent than most other countries