This discount rate is 7per cent a year. This means that net benefits in 20 years' time are reduced to about one quarter of the same net benefit today. With heavy early construction costs followed by decades of net benefits, this massively undervalues benefits in relation costs.

According to the authoritative guideline on this matter, Risk in Cost-Benefit Analysis, Report 110 by the Bureau of Transport and Regional Economics, 2005, the discount rate in an analysis of this kind should reflect only the "social time preference" for economic benefits. Such a discount rate can be determined by the difference between inflation and the long-term bond rate for AAA-rated governments; in other words, the real, risk-free rate of return.

The BTRE report states this figure is usually between 2 and 4per cent a year, but it may currently be far lower than even this, and close to zero. 2006 guidelines from the Department of Finance support the BTRE report, while the UK Treasury recommends a discount rate of 3.5per cent.

The business case should be revised, with a discount rate of, at most, 2per cent. This will give a much fairer picture of the net benefits of the light rail proposal.

Paul Pollard, O'Connor

Brendan Lyon, chief executive of Infrastructure Partnerships Australia, argues that a light rail contract should not be torn up post-election ("Canberra Liberals on the wrong side of light rail debate", Times2, April 20, p5). Given his peak body represents the consortia bidding for light rail, trying to get a slice of the taxpayer pie, I'd expect nothing less.

It's nevertheless concerning that both Lyon and Simon Corbell act like the Liberals have already won government and it is they who have to decide between proceeding with a project they do not believe in, or stopping it and paying a cancellation fee petulantly inserted into a secretive election-eve contract by Corbell.

But, in reality, it is the government who has the choice. The solution is simple. The government should delay signing the contract until after the election. Let the people decide. If Labor wins, contracts are signed. Construction is delayed a few months – big deal. If the Liberals win, contracts are not signed. Either way, Shane Rattenbury may not get his tram on schedule, or at all, but at least the Canberra the voter/ratepayer wins by getting a say, there is no cancellation fee, and sovereign risk does not become an issue.

Max Kwiatkowski, Holder

The two recent reports on the Eastman scandal ("Eastman tries to stay second murder trial", April 18,p3 and "Police push denies Eastman sensitive evidence", April 17, p1) raise yet more questions about the administration of justice in the ACT.

The first report informs us Justice Anthony Whealy has ruled it is in the public interest to keep secret – that is, to withhold – from Eastman's lawyers some of the evidence they believe would be exculpatory of Eastman. Withholding evidence from the defence rings a bell and is certainly not in the interests of justice and, therefore, cannot be in the public interest.

The second report informs us that Eastman has sought to have Justice Whealy remove himself from hearing Eastman's stay application, to be heard in July, because of a possible apprehension of bias by Justice Whealy towards Justice Michael Adams, QC, who, it appears, worked with Justice Whealy when Justice Adams was the prosecutor in Eastman's 1995 trial.

Unsurprisingly, the DPP's present counsel, Murugan Thangaraj, SC, has opposed Eastman's request, reportedly saying that "Mr Adam's conduct was found to have been proper ... by the inquiry into Eastman's conviction ...".

But one can't help but take notice of the fact that Annexure 11 of the report of the board of inquiry, dated April 15, 2014, is headed "Notices of proposed adverse comment — DPP, ADAMS, Justice Michael and IBBOTSON, John".

Peter Cormick, Deua River Valley, NSW

I enjoyed Ian Warden's "It's time to bring back the oyster wenches" (April 19, p18) and his inner struggle about people eating and drinking loudly at the cinema during the Russian film Leviathan.

While his inner fogey and thinking man sides fought over whether to complain about or celebrate the noise, his inner pedant must have been distracted. Leviathan is not about the "sheer misery of Siberian life". It is set near Murmansk in north-west Russia , not that far from Finland and Norway.

Andrew Gosling, Stirling

If Fredrik Limacher (Letters, April 15) were still sending children to school, they may well have been "a potential reservoir of infection", in spite of being vaccinated.

He is confusing vaccination with immunisation. Being vaccinated doesn't mean you have been immunised.

Some vaccines have been reported as having an efficacy as low as 50per cent and questions are being raised over the effectiveness of others – whooping cough, for example.

If you are serious about it, maybe those being vaccinated should be required to have blood tests conducted to ensure they have the necessary level of protection. This is, of course, assuming the bug hasn't mutated in the meanwhile, rendering the vaccine obsolete.

As for the comparison with dogs. You have noticed that the triple antigen is now three-yearly, rather than an annual? This rescheduling occurred because owner's pets were developing significant health problems from being over-vaccinated.

Chris Morgan, Evatt

It is far from inspiring to see Reserve Bank governor Glenn Stevens, on his world travels, selling down Australia. This time it is in the US, where the Australian currency gets weaker every day, thanks to his efforts. By the use of Howard's one-sided US Free Trade Agreement, US predators (helped by Stevens' efforts to get the Australian dollar below US75¢) can now buy more Australian businesses. Stay home, governor, and let Australia retain at least some ownership of its hard-won assets, now being picked off one by one.

Rex Williams, Ainslie

At last, a Foreign Minister who combines diplomatic savvy with diplomatic courtesy and respect for the culture of the country to which she travels, without whines about the lack of English subtitles on in-flight videos, unlike her predecessor ("Tehran to share Iraq IS spy info", April 20, p1).

Combine that with a steely determination not to fold in the cut-throat negotiation game and we can be very proud of Julie Bishop. As for the headscarf, as usual, Julie didn't put a foot wrong, and I'll bet even the Iranians were mightily impressed.

Christina Faulk, Swinger Hill

Having grown up in an age when the majority, including the non-religious, understood and backed religious moral values, and drug and sex addicts had consciences and understood their place in society, even while struggling with their own personal demons, I am more and more feeling like a conservative dinosaur who is becoming simply asocial bystander struggling tomaintain some relevance in modern society.

But I have the utmost respect foranyone who is trying to make adifference, and I thank God that wehave a Prime Minister who espouses Christian morality, and we should be behind him 100 per cent in his efforts to restore religious values to our society.

Claude Whiltshire, Queanbeyan, NSW

In May 1939, the ship St Louis left Hamburg, Germany, with nearly 1000 Jews fleeing the Nazis. An estimated half of the passengers later died, after both the United States and Cuba rejected their pleas for refuge and a 40-day journey took them back to Europe.

This week, HMAS Choules, after intercepting refugee boats on the high seas, returned 50 asylum seekers to Vietnam, following closelyon the heels of the death ofMalcolm Fraser, who facilitated the settlement of so many Vietnamese refugees in 1975.

God knows what these people will face on their forced return, but it won't be pretty.

One's thoughts are with the crew of the Choules this Anzac week as they go down in history as the Coalition's actors in the 21st-century version of the Voyage of the Damned.

Dallas Stow, O'Connor

I was pleased to read Dr William Maley's second letter (April 17) on asylum seekers, this time setting out his views on this thorny subject, which is progress of a kind.

Maley does not explain what he is trying to achieve, but one can gather that he wants the offshore detention centres emptied and closed, the speed of processing reduced andimproved resettlement arrangements in Australia. If this summation is correct, then we are not far apart. However, I doubt that we would agree on how to achieve this outcome.

As a pragmatist, the thought ofincreasing the pull factors by dismantling a system that is working very well does not make sense.

In the past the high inflow of asylum seekers not only resulted in unacceptable deaths at sea, but the movement exceeded our capacity toprocess people, resulting in overcrowded detention centres andall the misery that entailed.

Add to this the enormous initial and ongoing costs of sorting out truerefugees from the economic migrants plus supporting large numbers of dependent people outside our formal arrangements and we can only reflect on a deeply flawed policy that should never be revisited. If Maley's aim is to accept all comers into Australia and deal with them onshore, I fear he is risking an even bigger problem thanthe debacle of the recent past. Itwould not take long for the unchecked arrivals to rise exponentially to a point that was unacceptable to the Australian people and once again we would be faced with the dilemma of what to do to stem the flow. There is also a clear and foreseeable risk that large numbers would die at sea unless we did something to mitigate the risk.

If, for example, we used the navy to carry out this task, imagine the magnification of the pull factor and the vicious circle we would create. Certainly a durable regional solution does appear to have merit and is worth pursuing as a long-term goal.

This brings me back to my original point that created the fuss. It's better to carry on, empty the detention centres, stop the deaths at sea, deprive the people smugglers of their trade and work towards a bi-partisan arrangement that is regional, generous, targeted and sustainable.

H. Ronald, Jerrabomberra, NSW

Everyone is warning about a super tax ripoff in the coming budget. No one seems to have noticed the ripoff in last year's budget. For this year and the next two years, the Temporary Budget Repair Levy will apply to superannuation lump sums received by retirees. This will be the case even if the super payment is supposed to be tax free, because itwas taxed in the super fund.

I have a letter from the Treasury confirming this and saying that the repair levy is working as intended as it applies to superannuation lump sums. So money accumulated over awhole working life will attract the levy as if retirees were "high-income earners". Fair?

Mark Carter, Amaroo

In spruiking his vague plans to tax the ill-gotten gains of multinationals operating in Australia, Treasurer Joe Hockey asserts we "can learn a lot from what the British are doing with their so-called Google tax" ("Google tax: Hockey top adviser attacked plan in former role", canberratimes.com.au, April 20).

Given reports that Britain's treasury has estimated the Google tax will collect only $48 million next year, it seems Robert Jeremenko's characterisation of the tax as a "soundbite" would apply equally toMr Hockey's announcement.

John Richardson, Wallagoot, NSW

I was sad to read that the last four Marist brothers (one of whom is still teaching) will be departing the community in the middle of the year ("End of era as Marist Brothers prepare to leave", April 18, p9). This departure ends a tenure of 55 years by the brothers.

My family lived in Queanbeyan when the brothers decided to set up a primary school in the town. Because I and my brothers had attended a Marist boarding school in Sydney, we were approached to assist in integrating the brothers into the community.

Brother Mark May was commissioned to establish the school, which opened in the early '60s with headmaster Brother Conleth and three other brothers. Brother Mark was also instrumental in the planning, design and project managing of Marist College, Pearce, which began in 1968. Brother Crispin was the inaugural principal, followed by Brother Mark. Over the past 47 years, Marist College has grown into one of the finest educational institutions in the country.

Over 9000 students have graduated since the first graduating class of 1975. Many of these students have gone on to become leaders in many fields of endeavour.

Of the many dedicated brothers that have taught at the college during that period, I would like to single out three special teachers whose dedication to their vocation could only be described as outstanding: Brother Mark May, Brother Jerome Hickson and Brother Anthony Atkinson.

Much is owed by the Canberra community for the unselfish dedication of these fine men. Unfortunately, these same men have had their good works tarnished by the deeds of a minority and exacerbated by a vendetta from a few misguided journalists.

Brendan Ryan, Mawson

TOO MANY STOPPAGES

The reason I am not a regular at Canberra's Brumbies games has nothing to do with "Love over money" or the weather ("Love over money", April 19, p44). Rather it is (i) Stoppages during play: too frequent and too long, and (ii) Referees' influence on the result of the game – especially penalty rulings – especially those late in the second half.

R.J. Wenholz, Holt

BALANCING THE BUDGET

Will the federal budget ever be balanced ("No date set for budget surplus, says Hockey", April 20, p2)? Not in this decade or the next. Treasurer Joe Hockey was a fake from day one. Now he has proven it.

Victor Diskordia, McKellar

A PRECIOUS RIGHT

Chris Whyte (Letters, April 20) admits to voting informal for many years and offers to change if an incoming ACT government agrees to some naive and unrealistic demands. I think people who waste the precious right to vote forgo the right to criticise the government they get. In fact, people like Chris Whyte are among the reasons why Australian politics is so debilitated. It's always better to try to be part of a solution.

David Townsend, Curtin

'HAND-RINGING' NOTION

I was unable to finish reading Nicholas Stuart's column ("Value for money isn't easy", Times2, April 21, p1) because I was distracted by the interesting notion of "hand-ringing". Is this some Newtonian third law equal and opposite reaction to ear-ringing? Or is it just the noise you get when you hit a submarine you don't like?

Gerard Barrett, Latham

SOLDIERS REAL HEROES

Anzac Day will see AFL, rugby league and rugby union games played throughout Australia. During these games commentators sometimes refer to players as being brave and courageous and sometimes heroes. Brave and courageous is going to war for your country and not player actions during a game. Heroes are those who put their life on the line on the battlefield not the sporting field.

Greg Blood, Florey

Like Jenna Price, I am disappointed at some of the recent rather vulgar attempts to commercialise Anzac Day ("How I fell for Anzac Day, and why I'm over it", Times2, April 21, p5). What irks me more, however, is that the "very open-minded" Jenna Price felt the need to put her knife into an innocent bystander who was presumably moved and reverent at the interment of an unknown soldier – one of 60,000 Australians who died on foreign soil, laying down his life for Australia.

Virginia Berger, Barton

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