If you're minding your own business chances are you wouldn't be busted as you wouldn't be acting in a suspicious manner and therefore wouldn't be giving the police any real reason to search you let alone be aware of your drug-induced state. Police, in Victoria at any rate, can't just go around searching people and fucking with their civil liberties, they need reasonable grounds to do so. I assume it's the same in WA.
As for possession of one pill, I imagine the penalties are similar to those in Victoria, as they are in SA and NSW, which is a maximum $3000 fine(unlikely especially for a first offence/clean record and such a small quantity) and at the most 1 year in prison(even more unlikely).
Generally speaking, in situations concerning first offenders, handing out punishment for minor drug offences is to a large degree at the courts discretion. Meaning that, if you can show that you're a valued member of society(eg. holding down a job, good family life, contributing to the community, going to church, teaching blind people to read, etc) the court is very unlikely to hand down a severe sentence.
[edit: as with any situation concerning legal infringments which require court appearance, the most sensible thing to do(apart from not get caught) is to seek representation immediately, if that means only court appointed legal aid then so be it. A criminal record is not something you want especially when it's for life.]
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One more hour.
[This message has been edited by Prometheus (edited 25 October 2001).]