THE people of Scotland have been offered a “light at the end of the tunnel” in the form of various potential relaxations to lockdown - but warned they will only get there if they double down on their compliance.

That was the core message at the heart of Nicola Sturgeon’s briefing on Tuesday as she stressed that the fight against coronavirus has reached a “critical stage” where it would be “easy to go in the wrong direction”.

Current estimates put Scotland’s R number - the reproductive rate of the virus - between 0.7 and one. Closer to 0.7 and Covid transmission would be in a sustained decline; closer to one and it would be on the cusp of accelerating out of control again as soon as lockdown is eased.

READ MORE: Scientists call for two-track approach that would free majority from lockdown earlier 

That is why the next few weeks are so crucial. Driving the R number down to 0.7 or lower would give the Government the “headroom to cope”, as Ms Sturgeon put it, with the inevitable increases in infection rates that would follow the lifting of any of the current control measures.

Think of it as a precariously balanced see-saw where increased compliance with lockdown tilts the R number down, and a growing percentage of the population flouting the guidance tilts it up.

The First Minister has sought to incentivise cooperation by outlining the possible freedoms and benefits which could be re-introduced before the end of May if the evidence says it is safe to do so (ie. the R number is falling).

Schools could be partially re-opened; some NHS elective procedures and screening could resume; people could be allowed to meet up with a small ‘bubble’ of friends and family outwith their household; more time outdoors for exercise; and manufacturing, retail and construction businesses could be allowed operate again, as long as workplaces could be made safe and commuters did not overcrowd public transport.

None of this is guaranteed, however. Rather, it is a carrot for a restless population bored of staying at home and lulled into a false sense of security by Boris Johnson’s “past the peak” proclamations.

READ MORE: People who test positive for Covid could be offered accommodation 'away from household' in new test, trace and isolate phase

And this is the crux of the problem the Scottish Government is facing. If the public take on board the FM’s pleas, stick with the rules, and even increase their compliance, then the R number will reduce, some small freedoms will be re-introduced, and the strategy will be seen as a success.

But what if they don’t? Already there are signs that lockdown is fraying: statistics point to more car traffic on the roads and more bus journeys being taken; anecdotally people speak of their local neighbourhoods growing busier; some cafes have opened for takeaways and motorists were seen queued up in their hundreds outside a Costa Coffee Drive-thru in Glasgow at the weekend. Warmer weather and sunshine won’t help matters.

If this continues, and the R number goes up not down, will the Scottish Government really countenance extending or even toughening up on its lockdown measures in the face of a clear pushback from the population that would render it ineffective anyway?

There is of course more to weigh up than just suppressing the virus. There are the detrimental impacts of lockdown on physical and mental health.

While the focus has been on Covid, some cancer patients have seen their surgery or chemotherapy put on hold for their own safety and offered potentially less effective treatments such as radiotherapy or immunotherapy in the meantime. There are also thousands in pain as they wait for hip or knee replacements or struggling with ever-deteriorating vision while their cataract removal is delayed. That cannot continue.

Workers in frontline mental health have described people presenting in crisis who had no prior history of psychiatric illness. That is probably only the tip of the iceberg.

The economy has nosedived and furlough has been extended until the end of June. But what if the UK Government (who seem in a greater hurry to reach ‘new normal’) suspend it after that or impose stricter criteria? The ripple effect for public health of soaring unemployment and loss of income is well-known.

READ MORE: Only 56% of Scotland's virus testing capacity used 

So we really are approaching a critical moment - for the Government.

One escape route touted by scientists this week is a two-tier “segmenting and shielding” approach that would allow the majority of the population to resume something closer to normality sooner.

Younger people and those without underlying conditions or co-morbidities would be ‘released’ while those at higher risk continue to be “shielded” from the general population.

This has its appeal, but deciding who to shield could be complicated. A blanket restriction based on age would be controversial.

But if decided by health, does that mean we should include obesity (increasingly being linked to a higher risk of serious complications and death from Covid) and confine nearly a third of Scotland’s adult population indoors?

Lockdown cannot go on forever. But exiting will be far from simple.