Here is some sage advice for anyone about to use the internet for anything other than pleasure: if you don't want to get into trouble, don't type it in. This has been made crystal clear to me after communicating with some experts in the field of online security. Unless you are 100 per cent sure of your encryption or blocking software - and you never can be - forget about online banking, e-mails advocating overthrowing the government or expressions of devotion to your extra-marital lover. Someone, somewhere, can access the information and, if they want to, take your money, send you to jail or tell your spouse.
Two mainland journalists who circulated their ideas on democracy using the US-based company Yahoo's services know this only too well. They are both serving 10-year prison terms after the firm's Hong Kong office handed over e-mail and group list records on request from Beijing. Yahoo claims that a lawsuit brought against it in San Francisco should be dismissed because a US court has no jurisdiction over Chinese government actions against its citizens. The hearing is due to be held on November 1.
Beijing is widely criticised internationally over its state controls on the internet, used by up to 130 million people. Sites considered 'not in the national interest' are censored; from tomorrow, it is rolling out a new means of monitoring users that goes beyond software, information requests to service providers, and the tens of thousands of security police. Animated icons of police officers will appear on internet screens every 30 minutes and can be clicked on to report 'illicit activities' directly to the Public Security Bureau.
Mainland authorities are obviously not the only ones who use the internet to spy on their citizens. Governments the world over, particularly since the terrorist attacks in the US on September 11, 2001, have changed legislation to make accessing such information easier. Through its Echelon surveillance system, the US government gathers information about suspected criminals beyond American borders.
American Civil Liberties Union spokesman Jay Stanley said Washington's electronic data-gathering activities, although restricted domestically by privacy regulations, were 'worsening'. The laws, he contended, were 'being eroded around the edges in different ways'.
The president and chief executive of International Risk, Steve Vickers, a former Hong Kong police criminal investigations chief, said that most governments had the ability to collect and collate electronic information of all sorts, although they also generally needed co-operation from service providers. A few - those of the United States, Britain and Australia among them - also had agreements to tap data from communications satellites.
Anything done in the electronic medium left what he termed a 'footprint in the sand'. While it remained visible - or in the case of, say, an e-mail, undeleted on either the senders' or recipients' internet providers' servers - it could be tracked down and reviewed by whoever wanted to check it out.
There are, of course, ways of getting round the problem. The lobbying organisation Cyber-Rights & Cyber-Liberties (UK) uses servers based in Canada that delete e-mail and other internet records after they are read to get round British regulations. Its founder and director, Yaman Akdeniz, advocated a cautious approach to internet usage. Society was moving towards an Orwellian nightmare, he said, in which we were constantly being watched and listened to.
Of course, users of Yahoo, Google, Facebook or any internet-based service only have themselves to blame if they end up in trouble: the contract above the 'I agree' button they click on when they sign up absolves the providing company of responsibility.
The rule of thumb, as I stated at the outset, is that if you want to play safe on the internet, stick to playing. If you have sensitive information or subversive thoughts, keep them well away from anything online. As for me, I've invested in an HB pencil, some paper and a shredder to ensure my secret thoughts stay that way.
Peter Kammerer is the Post's foreign editor