The only alternative is to display consistency in considering her legal obligations and instruct the ACT police to charge the mother for, and the doctor and hospital staff for complicity in, the administration of a prohibited substance to a minor.

It is said comparisons are odious, so I will refrain from any comparison with other contentious legislation that has passed before our town council.

Gary J. Wilson, Macgregor

Of course the decision on medical cannabis should not only be based on a poll, but on the evidence (Collis Parrett, Letters, July 30). The research evidence and lived experience shows cannabis can provide relief. For example, the NSW case of Lucy Haslam's son, diagnosed with terminal bowel cancer and who is constantly nauseous from treatment, losing weight and unable to eat. That was until he tried cannabis.

Also for example, the case of the treatment of CDKL5, for which there is no known cure, but there is relief by cannabis oil (CT, p1, July 31). Parrett and others interested in the medical evidence could start with the Medical Journal of Australia 199(11) of December 16, 2013, in the article ''(Re) introducing medicinal cannabis'' by Laurence E. Mather et al, which says ''cannabis has genuine medicinal utility''.

Of course the supply of cannabis must be regulated. The ACT exposure draft of the bill for medical cannabis comprehensively covers the medical conditions and how supplies are to be regulated.

MPs need to know there is good reason for legislating and that there is good community support. Here the result showing 72.4 per cent in support, as reported by the household survey, comes in.

The boxes have been ticked and supplemented by the knowledge that the suffering of people in the last period of their life can be relieved. These people should not be criminalised for their use of a herb that brings relief to them or a family member.

B. McConnell, Higgins

Tony Abbott said this week in relation to Russia that he objects to large countries interfering in the affairs of small ones. It's a pity that when he was a minister in the Howard government in 2003, he did not object to the invasion of Iraq by the US, Britain and Australia. While Mr Abbott and Julie Bishop rightly have concern for the victims of the Malaysia Airlines plane crash, they appear to have no interest in the many thousands of innocent Iraqi civilians who have lost their lives or been driven from their homes since the Abbott-sanctioned invasion of their country.

John Davenport, Farrer

Jack Waterford (''MH17: Expect truth but not justice'', July 23) seems to say the shooting down of civilian aircraft in war is generally done by mistake - a form of collateral damage. Not always, Jack. In September 1978, Air Rhodesia Flight 825 was shot down at Victoria Falls. Fourteen of the 52 people on board survived the crash landing. All but three of the initial survivors - including children - were then murdered on the ground by the group that had downed the aircraft. In February 1979, Air Rhodesia Flight 827 was shot down at Victoria Falls by the same group. All 59 on board were killed. Both aircraft were destroyed by Soviet-supplied Strela ground-to-air missiles.

Compared with the worldwide outrage about flight MH17, the world's response to the murder of 108 civilian holidaymakers 35 years ago was non-existent. As the Anglican Dean of Salisbury said at the time: ''The silence is deafening.''

In June 1980, the leader of the group responsible became a senior politician in the new Zimbabwe. He was Joshua Nkomo, and his master was Robert Mugabe. Mugabe remains president of Zimbabwe. He's never been asked to account for these two outrages. I guess he's not Vladimir Putin.

The rhetorical strategy of Mr McKerral's contributions on climate change is worth noting. Commence by setting up straw men before leading the bemused reader on a gallop through a series of assertions that when checked out usually turn out to be quoted out of context, involve cherry-picking of data and are misleading at best, if not actually wrong. Attempts by letter writers to the Canberra Times over the years to educate him on the basics of climate change remind me of the game of Whack a Mole. No matter how often you respond, he just keeps popping his head up.

Doug Hynd, Stirling

I thank J. McKerral (CT, Letters, July 29) for absolving many others and myself of any moral need to pay income tax and contribute to a sustainable society. After all, using J. McKerral's logic that Australia's greenhouse gas emissions are ''unnoticeable'' compared with China's, the tax I pay is, or should be, unnoticeable compared with that of Gina Rinehart or any of the other 50 wealthiest people in Australia. Though the Pareto principle means the loss of 20 per cent of tax revenue paid by the unnoticeable 80 per cent would result in shortfall. The question then must be: is a global greenhouse gas emissions target required? J. McKerral should support a target because, to quote: ''There is no way to accurately foretell future climate.'' Because of the unknown, a risk mitigation approach needs to be adopted. If the doomsayers are wrong, we all live on happily as the carbon tax didn't destroy the economy and the world is cleaner. If they're right, we will hopefully dodge the bullet of a wrecked economy and massive social upheaval under a severely changed global climate. On the matter of long-term jobs, electricity cost analysis clearly shows that in a few years, RET-encouraged clean energy will result in cheaper retail electricity prices. So jobs are safe with solar and wind powering our future. Rather than job losses, there will likely be more jobs beyond the renewables construction phase as millions of solar panels are replaced after their 20-ish-year lifespan. A full speed ahead, damn the torpedoes approach to the economy and the environment may have short-term gains, but it is an exceptionally high risk strategy. We may not get hit, but if we do will J McKerral be there to back up the bravado and pick up the pieces?

Mark Boscawen, Calwell

An exercise in mental arithmetic left me confused and bewildered after the report on the patronage expected for the proposed light rail network (CT, July 30, p3). I hope some of your resident pedants can disabuse me of my concerns.

Rounding up the estimates for weekday patronage in 2031 to 21,000, and assuming that weekends would have half that daily number, 126,000 punters would use the service each week, or about 6.5 million trips a year. If each trip costs $10, that's $65 million in annual gross revenue.

Now, assuming that the operating margin (revenue less expenses) of the light rail is a generous 10 per cent, this means there is free cash flow of $6.5 million a year to service the debt of $614 million. At an interest rate of 5 per cent the bill is $31 million a year, leaving a shortfall of $25 million.

A fare of $50 would cover that shortfall, but remember this means that commuters would be paying $500 a week for their travel, and there would still be no reduction in the loan principal. Also, given that very few public transport networks around the world are profitable (for example, ACTION buses operate with a zero to negative free cash flow), a 10 per cent operating margin is unlikely to be achieved. So how do we pay for this Green adventure?

In deference to the pedants, I am aware that there are some (slight) holes in my analysis and assumptions, but I am confident that the bigger picture is correct. And it is a frightening picture for ACT residents.

Wayne Ralph, Hawker

So former ACT chief minister Kate Carnell believes there is currently no business case for a light rail service between Canberra CBD and the Gungahlin Town Centre (CT, July 29, p3). Would this be the same Kate Carnell who thought there was a business case in the late 1990s for a high-speed train service between Canberra and Sydney?

Rob Ewin, Campbell

Now that the Liberals have had all their members, their Institute of Public Affairs, Kate Carnell and many instant experts join their well co-ordinated campaign to distract the elected government, it is time to stop this stuff and nonsense and for the ACT government to make sure it delivers to the electorate an innovative, 21st-century light rail system for the national capital.

Paul Costigan, Dickson

One must question the credibility of a government that launches a program, creates an authority to manage the implementation of the program, and then tells the authority to sell the viability and advantages of the program to the public.

Light rail is looming as a case study for future academic classes on how not to formulate, validate and implement government programs.

Ed Dobson, Hughes

M. Silex is wrong about Simon Corbell not being able to claim a mandate to construct the light rail (Letters, July 31).

The ALP went to the 2012 ACT election with a policy of aiming to begin construction on the light rail no later than 2016, and have it up and running by 2018. The Greens policy was to begin construction in 2015.

G. M. King, Narrabundah

It beggars belief that The Canberra Times publishes the rantings (in rap or not) of Ian Warden (''Yarralumla a NIMBY's paradise'', July 28, p8). He seeks to sensationalise through vilification of the entire population of Yarralumla, not to mention offending our Muslim friends at the local mosque.

Yarralumla residents are a strong community, proud of our historic roots, diverse social, cultural and religious ties, who welcome to our suburb large numbers of Canberrans and others (rowers, cyclists, walkers, coffee addicts, dog lovers and picnickers). Are we not entitled to an opinion about planned development in our suburb (which will double the population of the suburb without amenities, gridlock the roads and make parking at the small shopping centre harder than ever) without the constant prejudice, criticism and bias of The Canberra Times?

A few facts: the ACT government is not planning to develop the historic brickworks - no funding has been allocated for this purpose and it claims to be ''making it safe'' (code for mothballing); the ACT government is not planning sustainable development - in fact it is ignoring its own commissioned reports about the suitability of the site; and the ACT government has stated that the development is solely a revenue stream and funds from land sales will not go to the heritage redevelopment of the brickworks.

Yarralumla residents are not anti-development (we are not keen on eight-storey towers in any residential suburb of the ACT). We have worked tirelessly with the ACT government for several years to find a plan for sustainable development that is in keeping with the character of the suburb. We now seek that the ACT government withdraw the current plan and work with experts and residents to develop a better one.

Robyn Cooper, Yarralumla

Are ya feelin' bitter, Ian Warden,

With all the resentment you are hoardin'?

Your invective leaves us in no doubt

That Yarralumlans sure get up your spout!

But as you wail into your tissues

Your song neglects the central issues.

The Brickworks are an historic site;

Their preservation every Canberran's right.

Traffic, infrastructure and open space,

These are issues we must face.

But all of these your song bypasses;

You prefer to have a go at the ''upper classes''.

Jeanette Swayn, Yarralumla

Some years ago I worked for a store that sold industrial vacuum cleaners that the manufacturers assured us were OK for removal of asbestos dust. They were HEPA (high-efficiency particulate air) rated.

Recently, a cartridge on my colour laser printer failed, dumping toner into the printer, and I bought a small vacuum to clean it. This was HEPA rated.

After about a minute, the room filled with magenta dust and the vacuum died with a loud bang. Investigation showed the toner had bypassed the bag and settled on the motor causing a short circuit.

A check with the manufacturer revealed that the filtration system was designed to fail ''to protect the motor if the bag became clogged''. Magenta toner in the room is one thing but I am glad I was not trying to clean up amosite or crocidolite. DIY is not an acceptable asbestos solution.

Brian Wilson, Curtin

I was somewhat miffed by the unfortunate real estate headline about $1,000,000 sale in Curtain, in lieu of Curtin. I put this down to sight-deprived proofreading, but I realise it was probably caused by a fault in Windows. It is time to draw the matter to an end and wait for the residents of Condor and Forest to have their moment.

Phil Birch-Marston, Curtin

Salvation for Australia Post ? One assumes that the predicted reduction in mail services to three days a week will no longer be relevant once millions of job applications start heading out week after week.

Sue Dyer, Downer

BORDERLINE DECISION

Now Tony Abbott's MH17 recovery mission is stranded by the Ukrainian border protection forces, his options seem fastly reducing to people smuggling.

Chris Klootwijk, Macarthur

STEP UP, JOE

Why is Joe Hockey not offering up his dead body over the ''Indian solution'' proposed by Scott Morrison? How does this differ from the Malaysian solution offered by the Gillard government that so offended Joe?

K.L. Calvert, Downer

SCOTT'S GOT THE POWER

Frodo failed, Scott has the ring.

Mark Hartmann, Hawker

MEAN MANAGEMENT

Of all the nasty demoralising strategies management can use to beat up staff, ''spill and fill'' would have to be the worst (''Treasury staff told to reapply for jobs'', p1, July 30). The message this sends is ''we made a mistake when we appointed you''.

Paul Kringas, Giralang

CALLING THE TUNE

I enjoyed David Pope's cartoon today (Times2, p1, July 31), but I reckon he got it wrong. He should have depicted Martin Parkinson singing to Joe Hockey's tune.

Douglas Mackenzie, Deakin

WHO WON THE WARS?

I think I know who won World War II in Europe (probably the USSR, with some assistance from the West), but I am curious who N. Bailey (Letters, July 30) thinks won the wars in Vietnam, Afghanistan and Iraq by ''massive army invasion''. Submission of an aggressor by aerial bombardment did, of course, occur in WWII's Pacific theatre.

Peter Marshall, Captains Flat

DISLIKING TONY

Jenna Price's petulance is astonishing even by her low standards (''The Prime Minister should get back to work'', Canberra Times, July 29). Her visceral dislike for Tony Abbott is the only message, the rest is undergraduate tosh.

H. Ronald, Jerrabomberra

PALESTINIAN SACRIFICE

Some people in Canberra (Letters, July 28) think the Palestinians are Jesus figures, sacrificing their lives for the sins of the Nazis.

Kenneth Griffiths, O'Connor

PARK, THEN EXPRESS BUS

Dick Parker says there is no parking at Calvary after 9am, so he catches a bus (CT, July 31). Many city workers park at Calvary before 9am, walk down to Haydon Drive and catch the express bus to the city. They are not hospital employees or visitors.

T.W. Campbell, Bruce

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