Tobacco and alcohol went beyond decriminalisation to legalisation, and they kill approximately 16,000 annually, and hospitalise another 50,000. If any evidence rejects decriminalising of ice, these numbers do.

A liberal interpretation of drug laws, coupled with a broken-down rehabilitation system which is grossly inadequately funded, and doesn't prioritise long-term residential care, on the back of more decriminalisation, see a further increase in deaths from ice and other drugs.

The golden public health principle for drug epidemics which will witness a scourge on any society deviating from it, is primary prevention – which says simply if you don't dramatically reduce the epidemic will spread.

We have seen high success following the application of primary prevention with Ebola, MERS, and the Hendra virus, while our drug epidemic worsens.

Bill Shorten recently said Australians don't need new faces – they need new policies. His words echo those of James Carville who famously posted: "It's the economy, stupid" on the wall of Bill Clinton's campaign headquarters in 1992. Twenty-three years later in Australia, "It's the policy, stupid!"

Colliss Parrett, Barton

Daryl Dixon (Sunday CT, September 20, p18) is right on the mark about institutions short-selling on the stock market, facilitated by ATO policy and the ASX. In other commercial activities, selling property which you do not own, without the buyer knowing that you do not own it, is at least immoral and unethical, perhaps even fraudulent.

It is more so when the owner, namely the person whose investments are entrusted to the institution, does not know that the institution has lent that property, deliberately intending to drive down its value.

The aim in short selling is to advantage the seller to the detriment of the buyer. It is contrary to the basic function of the stockmarket, to raise capital for productive enterprise.

The ASX usually justifies shorting on the claimed increase in market liquidity and finding the "true value" of the share, whatever that means. In reality it just makes more money for the big players and the ASX itself, through increased brokerage, at the expense of smaller investors.

We all saw how the greed and unethical behaviour of large institutions caused the global financial crisis. The ATO, the ASX and the institutions need to take a long hard look at themselves in relation to their role in short selling.

Ross Ramsay, Farrer

The resurgent house orientation debate ("Liberals to repeal solar access rules if elected", Sunday CT, September 20, p3) is premised on solar panelling. If the house faces north, that is, the long axis runs east-west, half of the roof also faces north, giving a large area for panels which will, hopefully, eventually become cost effective.

Alternately, if the house faces east-west with the long axis running north-south, extended eaves, possibly with verandas, would shade the walls and windows for most of the day when the sun was high in the summer sky. Correspondingly, morning and afternoon solar exposure to alternate sides of the house would be increased in winter when the sun follows a lower trajectory across the sky.

Either model is dependent on block size, plot ratio and, most importantly, orientation of the street. With the current rate of shrinkage of size and increase of ratio, tenement development seems inevitable.

Gary J.Wilson, Macgregor

Political parties, whether in government or opposition, should replace leaders when necessary. We, the Australian public, do not elect our prime ministers, we only elect our representatives. Our prime ministers are chosen from and by the members of the party in government. Our representatives may affect who will be our prime minister, depending on which party forms government, and usually on the dominant faction within that party. If we don't like a party's leader, then we can change our choice of party.

If a party decides that it needs to replace a failed leader – whether leader of the opposition, prime minister, president, or general secretary – then it should do so, promptly, using the most appropriate means. To claim as some do that it should be left to us voters at the next election, allowing a failed leader to remain in office and make an even greater mess, is obviously nonsensical. It suggests one has not thought things through, or has a destructive or self-serving agenda.

The Liberal Party has demonstrated how a failed prime minister should be replaced. Hopefully the new government will do a good (not just better) job, or failing that, that it will be replaced by a party that will do a good job in government.

R.Neville, Fraser

Back in Canberra for a few days and there's (another) debate about moving Floriade. The best way to showcase the national institutions is to move it to the drab gardens which stretch from Old Parliament House down to the lake at Reconciliation Place.

This would allow the ponds and fountains there to be activated again. But can someone, anyone, please erect more sophisticated signage and installations for it at the major road entrances into the ACT and the ceremonial entrance along Northbourne Avenue?

As Canberra's major annual tourism attraction, it doesn't look very loved. Or worthwhile seeing.

Andrew Heslop, Albert Park, Vic

Mal Brough's remarks ("Annoyed Senators ready to go to war", September 23, p5) about putting voters in charge of easily numbering their Senate preferences to cast a formal vote should not evince criticism or threats of retribution.

In 1948, Liberal and Country Party MPs tried to amend a proposed continuation of draconian formality provisions when Dr Evatt introduced proportional representation for the Senate.

In 1983, Coalition MPs opposed the introduction of party boxes that have made it possible for interlocking numberings on group voting tickets, rather than electors' assessments, to result in the election of Senators with few first preferences.

If party boxes were abolished, official advertising could concentrate on alerting voters how to make the most of their opportunity to state the order in which candidates can have access to whatever remains unused of their single transferable vote.

Bogey Musidlak, convenor, Proportional Representation Society of Australia (ACT Branch)

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