If a US cabinet secretary was supposed to be visiting a secure location and that location had actually been broken into and festooned with decorations, there would definitely be an investigation here as well.
And the police were apparently telling the students that if they marched or demonstrated in matching t-shirts it would be considered a protest without a permit.
That definitely sounds overly strict, but it also is a lie by the students that it was not a political protest - since the white elephant symbol is a well-known political protest symbol in Singapore and has been worn and used in plenty of permitted protest marches and demonstrations.
"posted around the closed station" - where's the break-in?
"The government [of Singapore] has broad powers to limit citizens' rights and to handicap political opposition, which it used. Caning is an allowable punishment for numerous offenses. The following human rights problems were reported: preventive detention, executive influence over the judiciary, infringement of citizens' privacy rights, restriction of speech and press freedom and the practice of self-censorship by journalists, restriction of freedom of assembly and freedom of association, some restriction of freedom of religion, and some trafficking in persons." - State Department, March 6, 2007 (http://www.state.gov/j/drl/rls/hrrpt/2006/78790.htm)