Reasonable grounds?

"...[he] was not afforded the opportunity to attend voluntarily at the police station. In due course, the decision that he should be arrested will be the subject of some scrutiny".  So said the solicitor acting for a man arrested (at the almost obligatory ungodly hour of the morning) in the aftermath of - though not directly connected with - the Jimmy Savile business.  I hope these are not just empty words.  I have complained before about this modern police approach of arresting first and investigating later.  Whatever happened to the good old "helping the police with their enquiries"?  Even if you are later released without charge, an arrest goes on your record with possible serious consequences.