No, the roads belong to the people who pay for the privilege to use and maintain them.

Maybe it would have been best for all if in June 1817 Karl Drais kept going on his running machine after 13km and never looked back or threw it in the Rhine and walked home.

To try to shift the blame on to motorists for accidents that involve cyclists is a bit rich, considering what I witness these days.

Some people should not be allowed to ride bikes on the road at all, the same as some licensed car drivers should not be allowed to drive on our roads. What I object to is that over the years the ratepayers of this city have spent a fortune on public footpaths and cycle paths all around Canberra and a fifth of our roads are given to cyclists and still they want more.

It would be nice if the bike riders contributed (financially) to the road system as well. Maybe if the cyclists were charged a rego fee, CPI, Road Rescue fee, and a Road Safety Contribution they could then join our motorists group and have to right to complain and abuse one another without fear or favour.

Errol Good, Macgregor

In his letter 'Grocery mileage' (letters, June 15) Leon Arundel trades off the saving from cheaper groceries against the cost of driving to the cheaper stores.

The principle is fine, but unfortunately Leon uses the total cost of running a car instead of the incremental cost. The running costs determined by the NRMA, which Leon refers to, include a substantial element of fixed costs (mainly rego and insurance) which you pay whether you drive to the grocery store or not. The incremental cost (mainly fuel and maintenance) is what you actually pay for your decision to drive to the cheaper grocery store. As a rough guide the incremental cost can be estimated as double the fuel cost – which turns out to be substantially less than the NRMA total cost. There is also a component of depreciation, and this is in part fixed (based on time) and part incremental (based on km).

So you can afford to drive quite a lot further for your cheaper groceries than Leon suggests.

Roger Quarterman, Campbell

Leon Arundell (letters, June 15) thinks travel costs should be considered when comparing supermarket prices.

Thus IGA, which is more expensive, compares favourably with Coles, Woolworths and Aldi. I think travel costs should be excluded from the calculation to level the playing field. One reason being, for example, I can walk to a Coles, Woolworths or Aldi, but I would have to drive to an IGA.

Felicity Chivas, Scullin

Although I don't object in principle to speed humps, I do question the placement of some of them.

A speed hump has recently been installed in Battye Street near the AIS, but in the 60 zone rather than the 40 zone that adjoins it. As you are leaving the AIS, you make the reasonable assumption after passing the 60 speed limit sign that it is safe to accelerate to 60 km/h, but then immediately have to slow back down to 25 km/h to cross the speed hump.

If it is not safe to travel at 60 in this zone, why is the speed limit 60? If it is safe, why is there a speed hump? And why is the speed hump not in the 40 zone instead?

Andina Faragher, Macquarie

Did Mr Barr see the recent article about a cafe that recently banned takeaway coffee cups? Does Mr Barr know why? Because the plastic lining inside takeaway coffee cups is toxic to humans and the environment.

Mr Barr may have seen the TV show War on Waste which talked about this.

Is Mr Barr going to ask the bike riders whom he wishes to enjoy a coffee in the forest, to bring their own mugs?

P. A. Upward, O'Connor

As a regular visitor to Parliament House – for various meetings and semi-public events – I was appalled to encounter first-hand the unsightly "construction site" security fencing all around the Parliament House site to prevent ordinary members of the public from having access to the top of the site, as intended in the original building design.

Previously, like many others I assume, I occasionally enjoyed showing visitors over the grassed area as a demonstration of Australian egalitarianism.

I have never witnessed any members of the public engaging in anti-social or disruptive behaviour on the grassed areas.

Nor have I heard of any security issues actually arising from this free access. Indeed, the complete absence of any problems for almost 30 years since the 1988 opening of the building was probably the most significant phenomenon.

So I understand the National Capital Authority's apparent reluctance to warmly endorse the (politically motivated) statements by the (Liberal Party) Presiding Officers' request to allow the new and unnecessary security barrier to remain.

What will it take to reverse this pointless decision?

Trevor Wilson, Holder

There is an achievable solution to the issue of where the light rail should go from Civic to Woden ("NCA's light rail detour', canberratimes.com.au, June 16).

It could go under the lake. Starting from the Civic terminus of stage 1, it could go under City Hill and the lake and avoid a lot of disruption to current activities. It could resurface at an appropriate place in the Parliamentary triangle.

When the Acton tunnel on Parkes Way was constructed by digging a huge cutting then filling it in again, a nonconforming tender was submitted which would have achieved the same result by tunnelling, and at a similar cost.

I have no idea why that tender was not selected, but it was submitted by the people who constructed the Tuggeranong Sewer Tunnel of 9.6km so they had proven experience in this area.

David Hobson, Spence

Good on the government for standing up to red neck One Nation and The Nationals supporters who will be spitting chips over the gun amnesty.

N. Barry, Cumnock, NSW

The distressing stories from witnesses to the Grenfell Tower fire in London are timely reminders of why we need stringent government regulation.

The sole aim of the allegedly efficient "free market" is to make money. If savings can be made by using cheaper materials then "efficiency" necessitates "cheaper is better".

High-rises are not supposed to be consumed by fire in an hour or two. The harsh truths are these: first, living above the reach of fire brigade ladders means death in a fire; second, fire safety can only be guaranteed by regular, exacting government inspections of buildings and certified compliance; third, the private sector cannot be trusted to put resident safety before profit.

Regulation is not "red tape", it is the community's last defence against the skulduggery of business decision makers.

The people who die in fires are not the people who choose cheaper, unsafe materials over more expensive but fire-safe alternatives.

We need industrial manslaughter charges to make those responsible truly pay for the lives lost in the pursuit of profit.

Rod Olsen, Flynn

The complaints of the neighbour's representative committee about the poor firefighting, evacuation and alarms features of the London Grenfell Tower went unanswered for years. And now the cladding applied to the building only a few years ago is found to be the main conductor of the rapid spread of the flames that engulfed the building and its residents.

Many men women and children died painful and horrible deaths. Many more have suffered terrible and disfiguring burns. Where are our politicians denouncing capitalism's malpractices?

John Rodriguez, Florey

It is a shame that Tony Abbott and a handful of right-wing climate deniers in the Liberal Party is holding the country to ransom regarding renewable energy policy and refuse to act in the national interest.

We seem to get a daily warning from Mr Abbott on a variety of issues. This is the same man who said on Sky News on July 15, 2009: "If you want to put a price on carbon why not just do it with a simple tax? Why not ask motorists to pay more? Why not ask electricity consumers to pay more? It would be burdensome, but all taxes are burdensome." Then on July 24, 2009, Mr Abbott wrote a column in The Australian supporting Mr Rudd's ETS, stating an ETS "is a plausible means to limit carbon emissions". The hypocrisy of this man has no bounds.

Ray Armstrong, Tweed Heads South, NSW

Delivery of the Finkel report indicates that Australia is only just beginning to assess exactly how much coal-generated electrical capacity it will need to retain, and possibly even redevelop, over coming years while clean energy technology and distribution system updates become affordable and reliable.

Precipitate altruism at this stage could see the country crippled. The sale of Hunter River Valley coal holdings to an export-oriented foreign company could prove quite contrary to the nation's interests ("Chinese hurdle for Glencore coal bid", June 13, p31).

Gary J. Wilson, Macgregor

I am intrigued by the psychology of name-calling in place of argument by using facts and logic.

John McKerral has repeatedly presented evidence to support his scepticism of climate change dogma (I use this word advisedly).

Eric Pozza, on the other hand (along with other regular contributors to the climate change "debate" in your letters page), resorts to using emotion-charged terms like "denial" and accuses people of "lying through their teeth" and "[selling] their souls" for daring to express a dissenting point of view.

Everyone should "question the science", especially when the science is a new hypothesis, and even more so when it might be an untestable hypothesis. That is the difference between science and faith.

D. Zivkovic, Aranda

A lifelong civil libertarian – especially for the safeguarding of the individual against overreach by the state – I nonetheless find myself with some sympathy for moderating limited individual civil liberties in the name of collective security.

Stronger obligations to co-operate with national security questioning? OK. Stringent scrutiny of aspirant migrants and citizens? OK. Passport and travel restrictions in the cause of national security? OK.

Residency and citizenship revocation and deportation when serious obligations have been accepted then materially violated? OK. But such powers must only ever be exercised independently and judicially. Personal ministerial application of punitive measures breaches the constitutional separation of powers. It risks capricious, partisan, populist, poll-driven, decisions by blusteringly self-important, self-promoting politicians on a slippery slope towards excessive statism.

Mike Hutchinson, Reid

Rosslyn Williams says we have "moved on" from institutionalisation of the mentally ill (Letters, June 13). But only a small portion of the promised savings has been spent on community care.

Given persistent underfunding of alternative care, the effective outcome of deinstitutionalisation is that a good proportion (perhaps most) of mental health "care" now takes place, if at all, in the justice system, among the homeless, in grim boarding houses, or on the streets.

And mortality of the mentally ill with respect to the general population has continued to increase since deinstitutionalisation, despite advances in medical technology.

I understand Williams' concerns with civil liberties, and that some people held at the secure mental health unit have committed no criminal offences. But patients detained there have been assessed as being a possible danger to themselves or others.

If they have no family or social support network, setting them free to wander uncared for would certainly diminish their rights, safety and wellbeing, in my view.

David Roth, Kambah

MANUS A SORRY MESS

No doubt the $70 million awarded to the inmates on Manus Island will be shrugged off as petty cash by a government that has no qualms in keeping these asylum seekers out of the country. After all it pales into insignificance when one looks at the hundreds of millions Peter Dutton has squandered on his watch keeping these poor wretches imprisoned on that hell hole.

And what is even more gross is both sides of government share the guilt of this whole sorry mess.

D. J. Fraser, Currumbin, Qld

TRY A PEDESTRIAN BRIDGE

The NCA has aired a proposal to slow and constrict traffic flow whilst enlarging walkways on Commonwealth Avenue, including removing the clover leafs.

An alternative would be a pedestrian and bike bridge between Anzac Parade and Reconciliation Place. This would provide the grand vista for pedestrian visitors and a logical connection.

D. K. House, Canberra City

LEADING THE WAY

Observe the feminisation of British politics. The Prime Minister is a woman. Her chief vote-getter in Scotland is a woman. The leader of her government's prospective coalition partner is a woman. Her possible successor, the Home Secretary, is woman. And the Scottish Chief Minister is a woman. The only major non-woman is the Labour leader.

Michael McCarthy, Deakin

JUDGING THE JUDICIARY

The citizen is the most important person in our society and the court its servant. The PM had better make it clear in law that the community has the right to judge the judgments of the courts by public free speech.

John Dobinson, Herston, Qld

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